One Step closer to Mainstream: Quantum computing in silicon hits 99 per cent accuracy: University of NSW: Video

Australian researchers have proven that near error-free quantum computing is possible, paving the way to build silicon-based quantum devices compatible with current semiconductor manufacturing technology.

“Today’s publication shows our operations were 99 per cent error-free,” says Professor Andrea Morello of UNSW, who led the work with partners in the US, Japan, Egypt, and at UTS and the University of Melbourne.

“When the errors are so rare, it becomes possible to detect them and correct them when they occur. This shows that it is possible to build quantum computers that have enough scale, and enough power, to handle meaningful computation.”

The team’s goal is building what’s called a ‘universal quantum computer’ that won’t be specific to any one application.

“This piece of research is an important milestone on the journey that will get us there,” Prof. Morello says.

Quantum operations with 99% fidelity – the key to practical quantum computers.

Quantum computing in silicon hits the 99 per cent threshold

Prof. Morello’s paper is one of three published in Nature (“Precision tomography of a three-qubit donor quantum processor in silicon”) that independently confirm that robust, reliable quantum computing in silicon is now a reality. The breakthrough features on the front cover of the journal.

Morello et al achieved one-qubit operation fidelities up to 99.95 per cent, and two-qubit fidelity of 99.37 per cent with a three-qubit system comprising an electron and two phosphorous atoms, introduced in silicon via ion implantation. A Delft team in the Netherlands led by Lieven Vandersypen achieved 99.87 per cent one-qubit and 99.65 per cent two-qubit fidelities using electron spins in quantum dots formed in a stack of silicon and silicon-germanium alloy (Si/SiGe). A RIKEN team in Japan led by Seigo Tarucha similarly achieved 99.84 per cent one-qubit and 99.51 per cent two-qubit fidelities in a two-electron system using Si/SiGe quantum dots.

The UNSW and Delft teams certified the performance of their quantum processors using a sophisticated method called gate set tomography, developed at Sandia National Laboratories in the U.S. and made openly available to the research community.

Prof. Morello had previously demonstrated that he could preserve quantum information in silicon for 35 seconds, due to the extreme isolation of nuclear spins from their environment.

“In the quantum world, 35 seconds is an eternity,” says Prof. Morello. “To give a comparison, in the famous Google and IBM superconducting quantum computers the lifetime is about a hundred microseconds – nearly a million times shorter.”

But the trade-off was that isolating the qubits made it seemingly impossible for them to interact with each other, as necessary to perform actual computations.

An artist’s impression of quantum entanglement between three qubits in silicon: the two nuclear spins (red spheres) and one electron spin (shiny ellipse) which wraps around both nuclei. (Image: UNSW/Tony Melov)

Nuclear spins learn to interact accurately

Today’s paper describes how his team overcame this problem by using an electron encompassing two nuclei of phosphorus atoms.

“If you have two nuclei that are connected to the same electron, you can make them do a quantum operation,” says Mateusz Mądzik, one of the lead experimental authors.

“While you don’t operate the electron, those nuclei safely store their quantum information. But now you have the option of making them talk to each other via the electron, to realise universal quantum operations that can be adapted to any computational problem.”

“This really is an unlocking technology,” says Dr Serwan Asaad, another lead experimental author. “The nuclear spins are the core quantum processor. If you entangle them with the electron, then the electron can then be moved to another place and entangled with other qubit nuclei further afield, opening the way to making large arrays of qubits capable of robust and useful computations.”

Professor David Jamieson, research leader at the University of Melbourne, says: “The phosphorous atoms were introduced in the silicon chip using ion implantation, the same method used in all existing silicon computer chips. This ensures that our quantum breakthrough is compatible with the broader semiconductor industry.”

All existing computers deploy some form of error correction and data redundancy, but the laws of quantum physics pose severe restrictions on how the correction takes place in a quantum computer. Prof. Morello explains: “You typically need error rates below 1 per cent, in order to apply quantum error correction protocols. Having now achieved this goal, we can start designing silicon quantum processors that scale up and operate reliably for useful calculations.”

Global collaboration key to today’s trifecta

Semiconductor spin qubits in silicon are well-placed to become the platform of choice for reliable quantum computers. They are stable enough to hold quantum information for long periods and can be scaled up using techniques familiar from existing advanced semiconductor manufacturing technology.

“Until now, however, the challenge has been performing quantum logic operations with sufficiently high accuracy,” Prof. Morello says.

“Each of the three papers published today shows how this challenge can be overcome to such a degree that errors can be corrected faster than they appear.”

While the three papers report independent results, they illustrate the benefits that arise from free academic research, and the free circulation of ideas, people and materials. For instance, the silicon and silicon-germanium material used by the Delft and RIKEN groups was grown in Delft and shared between the two groups. The isotopically purified silicon material used by the UNSW group was provided by Professor Kohei Itoh, from Keio University in Japan.

The gate set tomography (GST) method, which was key to quantifying and improving the quantum gate fidelities in the UNSW and Delft papers, was developed at Sandia National Laboratories in the US, and made publicly available. The Sandia team worked directly with the UNSW group to develop methods specific for their nuclear spin system, but the Delft group was able to independently adopt it for its research too.

There has also been significant sharing of ideas through the movement of people between the teams, for example:

Dr Mateusz Mądzik, an author on the UNSW paper, is now a postdoctoral researcher with the Delft team. Dr Serwan Asaad, an author on the UNSW paper, was formerly a student at Delft. Prof. Lieven Vandersypen, the leader of the Delft team, spent a five-month sabbatical leave at UNSW in 2016, hosted by Prof. Andrea Morello. The leader of the material growth team, Dr Giordano Scappucci, is a former UNSW researcher.

The UNSW-led paper is the result of a large collaboration, involving researchers from UNSW itself, University of Melbourne (for the ion implantation), University of Technology Sydney (for the initial application of the GST method), Sandia National Laboratories (Invention and refinement of the GST method), and Keio University (supply of the isotopically purified silicon material).

Source: University of New South Wales

MIT – Researchers develop a roadmap for growth of new solar cells – Could become Competitive with Silicon

Perovskites, a family of materials defined by a particular kind of molecular structure as illustrated here, have great potential for new kinds of solar cells. A new study from MIT shows how these materials could gain a foothold in the solar marketplace. Image: Christine Daniloff, MIT

Starting with higher-value niche markets and then expanding could help perovskite-based solar panels become competitive with silicon

Materials called perovskites show strong potential for a new generation of solar cells, but they’ve had trouble gaining traction in a market dominated by silicon-based solar cells. Now, a study by researchers at MIT and elsewhere outlines a roadmap for how this promising technology could move from the laboratory to a significant place in the global solar market.

The “technoeconomic” analysis shows that by starting with higher-value niche markets and gradually expanding, solar panel manufacturers could avoid the very steep initial capital costs that would be required to make perovskite-based panels directly competitive with silicon for large utility-scale installations at the outset. Rather than making a prohibitively expensive initial investment, of hundreds of millions or even billions of dollars, to build a plant for utility-scale production, the team found that starting with more specialized applications could be accomplished for more realistic initial capital investment on the order of $40 million.

The results are described in a paper in the journal Joule by MIT postdoc Ian Mathews, research scientist Marius Peters, professor of mechanical engineering Tonio Buonassisi, and five others at MIT, Wellesley College, and Swift Solar Inc.

Solar cells based on perovskites — a broad category of compounds characterized by a certain arrangement of their molecular structure — could provide dramatic improvements in solar installations. Their constituent materials are inexpensive, and they could be manufactured in a roll-to-roll process like printing a newspaper, and printed onto lightweight and flexible backing material. This could greatly reduce costs associated with transportation and installation, although they still require further work to improve their durability. Other promising new solar cell materials are also under development in labs around the world, but none has yet made inroads in the marketplace.

“There have been a lot of new solar cell materials and companies launched over the years,” says Mathews, “and yet, despite that, silicon remains the dominant material in the industry and has been for decades.”

Why is that the case? “People have always said that one of the things that holds new technologies back is that the expense of constructing large factories to actually produce these systems at scale is just too much,” he says. “It’s difficult for a startup to cross what’s called ‘the valley of death,’ to raise the tens of millions of dollars required to get to the scale where this technology might be profitable in the wider solar energy industry.”

But there are a variety of more specialized solar cell applications where the special qualities of perovskite-based solar cells, such as their light weight, flexibility, and potential for transparency, would provide a significant advantage, Mathews says. By focusing on these markets initially, a startup solar company could build up to scale gradually, leveraging the profits from the premium products to expand its production capabilities over time.

Describing the literature on perovskite-based solar cells being developed in various labs, he says, “They’re claiming very low costs. But they’re claiming it once your factory reaches a certain scale. And I thought, we’ve seen this before — people claim a new photovoltaic material is going to be cheaper than all the rest and better than all the rest. That’s great, except we need to have a plan as to how we actually get the material and the technology to scale.”

As a starting point, he says, “We took the approach that I haven’t really seen anyone else take: Let’s actually model the cost to manufacture these modules as a function of scale. So if you just have 10 people in a small factory, how much do you need to sell your solar panels at in order to be profitable? And once you reach scale, how cheap will your product become?”

The analysis confirmed that trying to leap directly into the marketplace for rooftop solar or utility-scale solar installations would require very large upfront capital investment, he says. But “we looked at the prices people might get in the internet of things, or the market in building-integrated photovoltaics. People usually pay a higher price in these markets because they’re more of a specialized product. They’ll pay a little more if your product is flexible or if the module fits into a building envelope.” Other potential niche markets include self-powered microelectronics devices.

Such applications would make the entry into the market feasible without needing massive capital investments. “If you do that, the amount you need to invest in your company is much, much less, on the order of a few million dollars instead of tens or hundreds of millions of dollars, and that allows you to more quickly develop a profitable company,” he says.

“It’s a way for them to prove their technology, both technically and by actually building and selling a product and making sure it survives in the field,” Mathews says, “and also, just to prove that you can manufacture at a certain price point.”

Already, there are a handful of startup companies working to try to bring perovskite solar cells to market, he points out, although none of them yet has an actual product for sale. The companies have taken different approaches, and some seem to be embarking on the kind of step-by-step growth approach outlined by this research, he says. “Probably the company that’s raised the most money is a company called Oxford PV, and they’re looking at tandem cells,” which incorporate both silicon and perovskite cells to improve overall efficiency. Another company is one started by Joel Jean PhD ’17 (who is also a co-author of this paper) and others, called Swift Solar, which is working on flexible perovskites. And there’s a company called Saule Technologies, working on printable perovskites.

Mathews says the kind of technoeconomic analysis the team used in its study could be applied to a wide variety of other new energy-related technologies, including rechargeable batteries and other storage systems, or other types of new solar cell materials.

“There are many scientific papers and academic studies that look at how much it will cost to manufacture a technology once it’s at scale,” he says. “But very few people actually look at how much does it cost at very small scale, and what are the factors affecting economies of scale? And I think that can be done for many technologies, and it would help us accelerate how we get innovations from lab to market.”

The research team also included MIT alumni Sarah Sofia PhD ’19 and Sin Cheng Siah PhD ’15, Wellesley College student Erica Ma, and former MIT postdoc Hannu Laine. The work was supported by the European Union’s Horizon 2020 research and innovation program, the Martin Family Society for Fellows of Sustainability, the U.S. Department of Energy, Shell, through the MIT Energy Initiative, and the Singapore-MIT Alliance for Research and Technology.

After 40 Years of Searching, Scientists Identify The Key Flaw in Solar Panel Efficiency

Solar panels are fantastic pieces of technology, but we need to work out how to make them even more efficient – and scientists just solved a 40-year-old mystery around one of the key obstacles to increased efficiency.

A new study outlines a material defect in silicon used to produce solar cells that has previously gone undetected. It could be responsible for the 2 percent efficiency drop that solar cells can see in the first hours of use: Light Induced Degradation (LID).

Multiplied by the increasing number of panels installed at solar farms around the world, that drop equals a significant cost in gigawatts that non-renewable energy sources have to make up for.

New Efficient Solar Panels Coming to the Market in 2019

In fact, the estimated loss in efficiency worldwide from LID is estimated to equate to more energy than can be generated by the UK’s 15 nuclear power plants. The new discovery could help scientists make up some of that shortfall.

“Because of the environmental and financial impact solar panel ‘efficiency degradation’ has been the topic of much scientific and engineering interest in the last four decades,” says one of the researchers, Tony Peaker from the University of Manchester in the UK.

“However, despite some of the best minds in the business working on it, the problem has steadfastly resisted resolution until now.”

To find what 270 research papers across four decades had previously been unable to determine, the latest study used an electrical and optical technique called deep-level transient spectroscopy (DLTS) to find weaknesses in the silicon.

Here’s what the DLTS analysis found: As the electronic charge in the solar cells gets transformed into sunlight, the flow of electrons gets trapped; in turn, that reduces the level of electrical power that can be produced.

This defect lies dormant until the solar panel gets heated, the team found.

“We’ve proved the defect exists, its now an engineering fix that is needed,” says one of the researchers, Iain Crowe from the University of Manchester.

The researchers also found that higher quality silicon had charge carriers (electrons which carry the photon energy) with a longer ‘lifetime’, which backs up the idea that these traps are linked to the efficiency degradation.

What’s more, heating the material in the dark, a process often used to remove traps from silicon, seems to reverse the degradation.

The work to push solar panel efficiency rates higher continues, with breakthroughs continuing to happen in the lab, and nature offering up plenty of efficiency tipsas well. Now that the Light Induced Degradation mystery has been solved, solar farms across the globe should benefit.

“An absolute drop of 2 percent in efficiency may not seem like a big deal, but when you consider that these solar panels are now responsible for delivering a large and exponentially growing fraction of the world’s total energy needs, it’s a significant loss of electricity generating capacity,” says Peaker.

The research has been published in the Journal of Applied Physics.

High-Performance ‘Quantum Dot Mode-Locked Laser on silicon – Proven 4.1 Terabit-per-second transmission capacity – The Future of Telecommunications and Data Centers – UC Santa Barbara

Ten years into the future.

That’s about how far UC Santa Barbara electrical and computer engineering professor John Bowers and his research team are reaching with the recent development of their mode-locked quantum dot lasers on silicon.

It’s technology that not only can massively increase the data transmission capacity of data centers, telecommunications companies and network hardware products to come, but do so with high stability, low noise and the energy efficiency of silicon photonics.

“The level of data traffic in the world is going up very, very fast,” said Bowers, co-author of a paper on the new technology in the journal Optica. Generally speaking, he explained, the transmission and data capacity of state-of-the-art telecommunications infrastructure must double roughly every two years to sustain high levels of performance. That means that even now, technology companies such as Intel and Cisco have to set their sights on the hardware of 2024 and beyond to stay competitive.

Enter the Bowers Group’s high-channel-count, 20 gigahertz, passively mode-locked quantum dot laser, directly grown — for the first time, to the group’s knowledge — on a silicon substrate. With a proven 4.1 terabit-per-second transmission capacity, it leaps an estimated full decade ahead from today’s best commercial standard for data transmission, which is currently reaching for 400 gigabits per second on Ethernet.

The technology is the latest high-performance candidate in an established technique called wavelength-division-multiplexing (WDM), which transmits numerous parallel signals over a single optical fiber using different wavelengths (colors). It has made possible the streaming and rapid data transfer we have come to rely on for our communications, entertainment and commerce.

The Bowers Group’s new technology takes advantage of several advances in telecommunications, photonics and materials with its quantum dot laser — a tiny, micron-sized light source — that can emit a broad range of light wavelengths over which data can be transmitted.

“We want more coherent wavelengths generated in one cheap light source,” said Songtao Liu, a postdoctoral researcher in the Bowers Group and lead author of the paper. “Quantum dots can offer you wide gain spectrum, and that’s why we can achieve a lot of channels.” Their quantum dot laser produces 64 channels, spaced at 20 GHz, and can be utilized as a transmitter to boost the system capacity.

The laser is passively ‘mode-locked’ — a technique that generates coherent optical ‘combs’ with fixed-channel spacing — to prevent noise from wavelength competition in the laser cavity and stabilize data transmission.

This technology represents a significant advance in the field of silicon electronic and photonic integrated circuits, in which the primary goal is to create components that use light (photons) and waveguides — unparalleled for data capacity and transmission speed as well as energy efficiency — alongside and even instead of electrons and wires. Silicon is a good material for the quality of light it can guide and preserve, and for the ease and low cost of its large-scale manufacture. However, it’s not so good for generating light.

“If you want to generate light efficiently, you want a direct band-gap semiconductor,” said Liu, referring to the ideal electronic structural property for light-emitting solids. “Silicon is an indirect band-gap semiconductor.” The Bowers Group’s quantum dot laser, grown on silicon molecule-by-molecule at UC Santa Barbara’s nanofabrication facilities, is a structure that takes advantage of the electronic properties of several semiconductor materials for performance and function (including their direct band-gaps), in addition to silicon’s own well-known optical and manufacturing benefits.

This quantum dot laser, and components like it, are expected to become the norm in telecommunications and data processing, as technology companies seek ways to improve their data capacity and transmission speeds.

“Data centers are now buying large amounts of silicon photonic transceivers,” Bowers pointed out. “And it went from nothing two years ago.”

Since Bowers a decade ago demonstrated the world’s first hybrid silicon laser (an effort in conjunction with Intel), the silicon photonics world has continued to create higher efficiency, higher performance technology while maintaining as small a footprint as possible, with an eye on mass production. The quantum dot laser on silicon, Bowers and Liu say, is state-of-the-art technology that delivers the superior performance that will be sought for future devices.

“We’re shooting far out there,” said Bowers, who holds the Fred Kavli Chair in Nanotechnology, “which is what university research should be doing.”

Research on this project was also conducted by Xinru Wu, Daehwan Jung, Justin Norman, MJ Kennedy, Hon K. Tsang and Arthur C. Gossard at UC Santa Barbara.

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Next-Gen Lithium-Ion Batteries – Combining Graphene + Silicon Could it be the Key?

Researchers have long been investigating the use of silicon in lithium-ion batteries, as it has the potential to greatly increase storage capacity compared to graphite, the material used in most conventional lithium-ion batteries. By some estimates, silicon could boast a lithium storage capacity of 4,200 mAh/g—11 times that of graphite.

However, despite its benefits, silicon comes with its own challenges.

“When you store a lot of lithium ion into your silicon you actually physically extend the volume of silicon to about 3 to 3.8 times its original volume—so that is a lot of expansion,” explained Bor Jang, PhD, in an exclusive interview with R&D Magazine. “That by itself is not a big problem, but when you discharge your battery—like when you open your smart phone—the silicon shrinks. Then when you recharge your battery the silicon expands again. This repeated expansion and shrinkage leads to the breakdown of the particles inside of your battery so it loses its capacity.”

Jang offers one solution—graphene, a single layer sheet of carbon atoms tightly bound in a hexagonal honeycomb lattice.

“We have found that graphene plays a critical role in protecting the silicon,” said Jang, the CEO and Chief Scientist of Global Graphene Group. The Ohio-based advanced materials organization has created GCA-II-N, a graphene and silicon composite anode for use in lithium-ion batteries.

The innovation—which was a 2018 R&D 100 Award winner—has the potential to make a significant impact in the energy storage space. Jang shared more about graphene, GCA-II-N and its potential applications in his …

Interview with R&D Magazine:

 

           Photo Credit: Global Graphene Group

 

R&D Magazine: Why is graphene such a good material for energy storage?

Jang: From the early beginning when we invited graphene back in 2002 we realized that graphene has certain very unique properties. For example, it has very high electrical conductivity, very high thermal conductivity, it has very high strength—in fact it is probably the strongest material known to mankind naturally. We thought we would be able to make use of graphene to product the anode material than we can significantly improve not only the strength of the electrode itself, but we are also able to dissipate the heat faster, while also reducing the changes for the battery to catch fire or explode.

Also graphene is extremely thin—a single layer graphene is 0.34 nanometer (nm). You can imagine that if you had a fabric that was as thin as 0.34 nanometers in thickness, than you could use this material to wrap around just about anything. So it is a very good protection material in that sense. That is another reason for the flexibility of this graphene material.

 

 

Read More: Talga’s graphene silicon product extends capacity of Li-ion battery anode

Another interesting feature of graphene is that is a very high specific surface area. For instance if I give you 1.5 grams of single layer graphene it will be enough to cover an entire football stadium. There is a huge amount of surface area per unit weight with this material.

That translates into another interesting property in the storage area. In that field that is a device called supercapacitors or ultracapacitors. The operation of supercapacitors depends upon conducting surface areas, like graphene or activated carbon. These graphene sheets have, to be exact, 2630 meters squared per gram. That would give you, in principle, a very high capacity per unit gram of this material when you use it as an electron material for supercapacitors. There is are so many properties associated with graphene for energy applications, those are just examples, I could talk about this all day!

 

 

R&D Magazine: Where is the team currently with the GCA-II-N and what are the next steps for this project?

Jang: Last year we began to sell the product. In Dayton, OH, where we are situated at the moment we have a small-scale manufacturing facility. It is now about a 50-metric-ton capacity facility and we can easily scale it up. We have been producing mass qualities of this and then delivering them to some of the potential customers for validation. We are basically in the customer validation stage for this business right now.

We will continue to do research and development for this project. We will eventually manufacture the batteries here in the U.S., but at the moment we are doing the anode materials only.

R&D Magazine: What types of customers are showing interest in this technology?

Jang: Electrical vehicles are a big area that is growing rapidly, particularly in areas in Asia such as China. The electrical vehicle industry is taking the driver’s seat and is driving the growth of this business worldwide right now. E-bikes and electronic scooters are another rapidly growing business where this could be used.

Another example is your smart phone. Right now, if you continue to use your phone you may be able to last for half a day or maybe a whole day if you push it. This technology has the ability to double the amount of energy that could be stored in your battery. Electronic devices is another big area for application of this technology. 

A third area is in the energy storage business, it could be utilized to store solar energy or wind energy after it has been captured. Lithium-ion batteries are gaining a lot of ground in this market right now.

Right now, another rapidly growing area is the drone. Drones are used, not only for fun, but for agricultural purposes or for surveillance purposes, such as during natural disasters.  Drones are seeing a lot of applications right now and batteries are very important part of that.

R&D Magazine: Are there any challenges to working with graphene?

Jang: One of the major challenges is that graphene by itself is still a relatively high cost. We are doing second-generation processes right now, and I think in a couple of years we should be able to significantly reduce the cost of graphene. We are also working on a third generation of processes that would allow us to reduce the cost even further. That is a major obstacle to large-scale commercialization of all graphene applications.

The second challenge is the notion of graphene as a so-called ‘nanomaterial’ in thickness that a lot customers find it difficult to disperse in water or disperse in organic solvent or plastic in order to combine graphene with other types of materials, make a composite out of it. Therefor people are resistant to use it. We have found a way to overcome this either real challenge, or perceived challenge. We can do that for a customer and then ship that directly to the customer.

There is also an education challenge. It is sometimes difficult to convince engineers, they want to stick with the materials they are more familiar with, even though the performance is better with graphene. That is a barrier as well. However, I do think it is becoming more well known.

Laura Panjwani

Editor-in-chief R & D Magazine

Boosting lithium ion batteries capacity 10X with Tiny Silicon Particles – University of Alberta

U of Alberta chemists Jillian Buriak, Jonathan Veinot and their team found that nano-sized silicon particles overcome a limitation of using silicon in lithium ion batteries. The discovery could lead to a new generation of batteries …more

University of Alberta chemists have taken a critical step toward creating a new generation of silicon-based lithium ion batteries with 10 times the charge capacity of current cells.

“We wanted to test how different sizes of silicon nanoparticles could affect fracturing inside these batteries,” said Jillian Buriak, a U of A chemist and Canada Research Chair in Nanomaterials for Energy.

Silicon shows promise for building much higher-capacity batteries because it’s abundant and can absorb much more lithium than the graphite used in current lithium ion batteries. The problem is that silicon is prone to fracturing and breaking after numerous charge-and-discharge cycles, because it expands and contracts as it absorbs and releases lithium ions.

Existing research shows that shaping silicon into nano-scale particles, wires or tubes helps prevent it from breaking. What Buriak, fellow U of A chemist Jonathan Veinot and their team wanted to know was what size these structures needed to be to maximize the benefits of silicon while minimizing the drawbacks.

The researchers examined silicon nanoparticles of four different sizes, evenly dispersed within highly conductive graphene aerogels, made of carbon with nanoscopic pores, to compensate for silicon’s low conductivity. They found that the smallest particles—just three billionths of a metre in diameter—showed the best long-term stability after many charging and discharging cycles.

“As the particles get smaller, we found they are better able to manage the strain that occurs as the silicon ‘breathes’ upon alloying and dealloying with lithium, upon cycling,” explained Buriak.

The research has potential applications in “anything that relies upon energy storage using a battery,” said Veinot, who is the director of the ATUMS graduate student training program that partially supported the research.

“Imagine a car having the same size battery as a Tesla that could travel 10 times farther or you charge 10 times less frequently, or the battery is 10 times lighter.”

Veinot said the next steps are to develop a faster, less expensive way to create silicon nanoparticles to make them more accessible for industry and technology developers.

The study, “Size and Surface Effects of Silicon Nanocrystals in Graphene Aerogel Composite Anodes for Lithium Ion Batteries,” was published in Chemistry of Materials.

 Explore further: Toward cost-effective solutions for next-generation consumer electronics, electric vehicles and power grids

More information: Maryam Aghajamali et al. Size and Surface Effects of Silicon Nanocrystals in Graphene Aerogel Composite Anodes for Lithium Ion Batteries, Chemistry of Materials (2018). DOI: 10.1021/acs.chemmater.8b03198

Journal reference: Chemistry of Materials  

Provided by: University of Alberta

Watch a YouTube Video about an Energy Storage Company Tenka Energy, Inc., that has developed and prototyped the NextGen of silicon-lithium-ion batteries for EV’s, Drones, Medical Sensors ….

Tenka Energy, Inc. Building Ultra-Thin Energy Dense SuperCaps and NexGen Nano-Enabled Pouch & Cylindrical Batteries – Energy Storage Made Small and POWERFUL!

via @Genesisnanotech #greatthingsfromsmallthings #energystorage

MIT: Material (molybdenum ditelluride) could bring optical communication onto silicon chips

Researchers have designed a light-emitter and detector that can be integrated into silicon CMOS chips. This illustration shows a molybdenum ditelluride light source for silicon photonics. Image: Sampson Wilcox

Ultrathin films of a semiconductor that emits and detects light can be stacked on top of silicon wafers.

The huge increase in computing performance in recent decades has been achieved by squeezing ever more transistors into a tighter space on microchips.

However, this downsizing has also meant packing the wiring within microprocessors ever more tightly together, leading to effects such as signal leakage between components, which can slow down communication between different parts of the chip. This delay, known as the “interconnect bottleneck,” is becoming an increasing problem in high-speed computing systems.

One way to tackle the interconnect bottleneck is to use light rather than wires to communicate between different parts of a microchip. This is no easy task, however, as silicon, the material used to build chips, does not emit light easily, according to Pablo Jarillo-Herrero, an associate professor of physics at MIT.

Now, in a paper published today in the journal Nature Nanotechnology, researchers describe a light emitter and detector that can be integrated into silicon CMOS chips. The paper’s first author is MIT postdoc Ya-Qing Bie, who is joined by Jarillo-Herrero and an interdisciplinary team including Dirk Englund, an associate professor of electrical engineering and computer science at MIT.

The device is built from a semiconductor material called molybdenum ditelluride. This ultrathin semiconductor belongs to an emerging group of materials known as two-dimensional transition-metal dichalcogenides.

Unlike conventional semiconductors, the material can be stacked on top of silicon wafers, Jarillo-Herrero says.

“Researchers have been trying to find materials that are compatible with silicon, in order to bring optoelectronics and optical communication on-chip, but so far this has proven very difficult,” Jarillo-Herrero says. “For example, gallium arsenide is very good for optics, but it cannot be grown on silicon very easily because the two semiconductors are incompatible.”

In contrast, the 2-D molybdenum ditelluride can be mechanically attached to any material, Jarillo-Herrero says.

Another difficulty with integrating other semiconductors with silicon is that the materials typically emit light in the visible range, but light at these wavelengths is simply absorbed by silicon.

Molybdenum ditelluride emits light in the infrared range, which is not absorbed by silicon, meaning it can be used for on-chip communication.

To use the material as a light emitter, the researchers first had to convert it into a P-N junction diode, a device in which one side, the P side, is positively charged, while the other, N side, is negatively charged.

In conventional semiconductors, this is typically done by introducing chemical impurities into the material. With the new class of 2-D materials, however, it can be done by simply applying a voltage across metallic gate electrodes placed side-by-side on top of the material.

“That is a significant breakthrough, because it means we do not need to introduce chemical impurities into the material [to create the diode]. We can do it electrically,” Jarillo-Herrero says.

Once the diode is produced, the researchers run a current through the device, causing it to emit light.

“So by using diodes made of molybdenum ditelluride, we are able to fabricate light-emitting diodes (LEDs) compatible with silicon chips,” Jarillo-Herrero says.

The device can also be switched to operate as a photodetector, by reversing the polarity of the voltage applied to the device. This causes it to stop conducting electricity until a light shines on it, when the current restarts.

In this way, the devices are able to both transmit and receive optical signals.

The device is a proof of concept, and a great deal of work still needs to be done before the technology can be developed into a commercial product, Jarillo-Herrero says.

This paper fills an important gap in integrated photonics, by realizing a high-performance silicon-CMOS-compatible light source, says Frank Koppens, a professor of quantum nano-optoelectronics at the Institute of Photonic Sciences in Barcelona, Spain, who was not involved in the research.

“This work shows that 2-D materials and Si-CMOS and silicon photonics are a natural match, and we will surely see many more applications coming out of this [area] in the years to come,” Koppens says.

The researchers are now investigating other materials that could be used for on-chip optical communication.

Most telecommunication systems, for example, operate using light with a wavelength of 1.3 or 1.5 micrometers, Jarillo-Herrero says.

However, molybdenum ditelluride emits light at 1.1 micrometers. This makes it suitable for use in the silicon chips found in computers, but unsuitable for telecommunications systems.

“It would be highly desirable if we could develop a similar material, which could emit and detect light at 1.3 or 1.5 micrometers in wavelength, where telecommunication through optical fiber operates,” he says.

To this end, the researchers are exploring another ultrathin material called black phosphorus, which can be tuned to emit light at different wavelengths by altering the number of layers used. They hope to develop devices with the necessary number of layers to allow them to emit light at the two wavelengths while remaining compatible with silicon.

“The hope is that if we are able to communicate on-chip via optical signals instead of electronic signals, we will be able to do so more quickly, and while consuming less power,” Jarillo-Herrero says.

The research was supported by Center for Excitonics, an EFRC funded by the U.S. Department of Energy.

Silicon Solves Problems for next-Generation Battery Technology: University of Eastern Finland

Silicon — the second most abundant element in the earth’s crust — shows great promise in Li-ion batteries, according to new research from the University of Eastern Finland. By replacing graphite anodes with silicon, it is possible to quadruple anode capacity.

In a climate-neutral society, renewable and emission-free sources of energy, such as wind and solar power, will become increasingly widespread. The supply of energy from these sources, however, is intermittent, and technological solutions are needed to safeguard the availability of energy also when it’s not sunny or windy. Furthermore, the transition to emission-free energy forms in transportation requires specific solutions for energy storage, and lithium-ion batteries are considered to have the best potential.

Researchers from the University of Eastern Finland introduced new technology to Li-ion batteries by replacing graphite used in anodes by silicon. The study analysed the suitability of electrochemically produced nanoporous silicon for Li-ion batteries. It is generally understood that in order for silicon to work in batteries, nanoparticles are required, and this brings its own challenges to the production, price and safety of the material.

However, one of the main findings of the study was that particles sized between 10 and 20 micrometres and with the right porosity were in fact the most suitable ones to be used in batteries. The discovery is significant, as micrometre-sized particles are easier and safer to process than nanoparticles. This is also important from the viewpoint of battery material recyclability, among other things. The findings were published in Scientific Reports.

“In our research, we were able to combine the best of nano- and micro-technologies: nano-level functionality combined with micro-level processability, and all this without compromising performance,” Researcher Timo Ikonen from the University of Eastern Finland says. “Small amounts of silicon are already used in Tesla’s batteries to increase their energy density, but it’s very challenging to further increase the amount,” he continues.

Next, researchers will combine silicon with small amounts of carbon nanotubes in order to further enhance the electrical conductivity and mechanical durability of the material.

“We now have a good understanding of the material properties required in large-scale use of silicon in Li-ion batteries. However, the silicon we’ve been using is too expensive for commercial use, and that’s why we are now looking into the possibility of manufacturing a similar material from agricultural waste, for example from barley husk ash,” Professor Vesa-Pekka Lehto explains.

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Story Source:

Materials

provided by University of Eastern Finland. Note: Content may be edited for style and length.

EV Batteries: A $240 Billion Industry In the Making that China is Taking the Lead

Even those who consider themselves somewhat knowledgeable about the electric vehicle (EV) industry would be hard pressed to name more than a handful of EV battery suppliers.

Most would quickly name Japan’s Panasonic and South Korea’s Samsung and LG Chem, as well as reference the Gigafactoy that Panasonic and Tesla opened this past January in Nevada. A few of the more knowledgeable would also name BYD, a leading electric vehicle manufacturer in China that is also one of the world’s largest battery suppliers.

Other than those names, however, and perhaps one or two other lesser known players, the list would end there.

 

Nearly everyone would be surprised to learn that there are now more than 140 EV battery manufacturers in China, busily building capacity in order to claim a share of what will become a $240 billion global industry within the next 20 years. As in all things auto, EVs and the batteries that will power them promise to be big industries in China.

A $240 billion industry

The math is simple. Respected auto analysts like those at Bernstein, a Wall Street research and securities firm, are predicting that EVs will account for as much as 40% of global vehicle purchases in 20 years. Since almost 100 million vehicles are produced and sold globally, that means that the annual market for EVs will be 40 million, even if the total global vehicle build does not increase between now and then.

Assuming that battery prices reach parity with the $6,000 cost of an internal combustion engine, a $240 billion battery industry is now in the making. Due to its well-publicized problems combatting air pollution, China will lead the way in EVs, as well as in batteries.

Read more: Why China Is Leading The World’s Boom In Electric Vehicles

In order to meet projected demand, battery cell manufacturing capacity globally will need to increase dramatically, which is why China’s battery makers are aggressively expanding. When Tesla and Panasonic announced in 2014 their plans to build a “Gigafactory” capable of producing 35 Gigawatt hours (GWh) of battery cells every year, that was big news. (A GWh is equal to one million kilowatt hours.) After all, the entire battery capacity in the world at the time was less than 50 GWh.

A great deal has changed over the last three years, though. Led by China, battery cell manufacturing capacity has more than doubled to 125 GWh, and is projected to double again to over 250 GWh by 2020. Even that will not be nearly enough. Total cell production capacity will need to increase tenfold from 2020 to 2037, the equivalent of adding 60 new Gigafactories, during that period.

 

Shifting towards China

Battery technology originated in Japan; was then further developed by companies in Korea; and is now shifting strongly toward China. China’s cell production already has a larger share of global production than Japan’s, and China’s global market share is projected to rise to more than 70% by 2020.

This photo taken on May 22, 2017 shows a car passing new electric vehicles parked in a parking lot under a viaduct in Wuhan, central China’s Hubei province. (STR/AFP/Getty Images)

Rapid market growth for EVs in China, as well as the tendency for Chinese auto assemblers to use homegrown products, augurs well for China’s continued leadership in battery cell manufacturing. According to Roland Berger’s E-mobility Index Q2 2017 report, locally made lithium-ion cells are used in more than 90% of the EVs produced by Chinese manufacturers.

Read more: The Electric Car Market Has A ‘Chicken Or Egg’ Problem — And China Is Solving It

With so many Chinese companies hoping to enter the battery sweepstakes, China’s government is considering policies that will set minimum production capacities for battery manufacturers as a way to further strengthen its position as a global leader. Although not yet official, Beijing would like Chinese manufacturers to have a production volume of at least 3 to 5 GWh per year. Separately, Beijing released draft guidelines at the end of 2016 stipulating that battery manufacturers would need to have at least 8 GWh of production capacity in order to qualify for subsidies. As a signal to the market, the government is planning to back the development of only those battery companies with annual production capacities of 40 GWh or more.

Who the government is championing

While Panasonic is the world’s largest supplier of electric vehicle batteries globally, Chinese companies are catching up.

Based in Shenzhen, BYD — which stands for “Build Your Dream” — is a Hong Kong listed, Chinese car company that in 2016 produced almost 500,000 cars and buses, approximately 100,000 of which were EVs or plug-in hybrids. Consistent with BYD’s strategy of vertical integration, it also has 20 GWh of battery cell capacity and is China’s largest battery maker.

In 2008, a subsidiary of Warren Buffet’s Berkshire Hathaway invested $230 million in BYD, which at the time represented a 10% stake in the company. BYD is now valued in the marketplace at $16.9 billion.

Read more: China And The U.S. Supercharge The Growing Global Electric Vehicle Industry

CATL is another leading Chinese battery company. Founded in 2011 and headquartered in Ningde, Fujian province, CATL focuses on the production of lithium-ion batteries and the development of energy storage systems. With manufacturing bases in Qinghai, Jiangsu, and Guangdong provinces, CATL has 7.7 GWh of battery capacity and plans to have battery production capacity of 50 GWh by 2020. Like BYD, CATL is the type of company that the Chinese government wants to support and promote as a national champion.

Companies to watch

Other companies to watch are Tianjin based Lishen Battery and Hangzhou’s Wanxiang Group.

State Grid Corp. of China (SGCC) battery packs sit on display in the showroom of Wanxiang Group Corp. in Hangzhou, China in September 2016. (Photographer: Qilai Shen/Bloomberg)

Lishen has production bases in Bejing, Qingdao, Suzhou, Wuhan, Ningbo, Shenzhen and Mianyang, and plans to have 20 GWh of battery cell capacity by 2020. And Wanxiang is one of China’s largest private companies and one of the country’s leading automotive components suppliers. In 1994, Wanxiang established a U.S. company in Elgin, Illinois. Since then, Wanxiang has made over two dozen acquisitions in the United States, including A123, a battery maker that had gone into bankruptcy, in 2013, and Fisker Automotive in 2014.

The flip side to the coming Electric Revolution, of course, is that for every battery pack that is put into a vehicle, one less internal combustion engine is needed. While the growth of EVs will give rise to a large global battery industry, it will also make obsolete the substantial investments that have been made in global engine and engine component capacity.

Watch a Video on the NEW 

Tenka Power Max SuperCap Battery Pack for 18650 and 21700 Markets

Super Capacitor Assisted Silicon (and graphene) Nanowire Batteries for EV and Small Form Factor Markets. A New Class of Battery /Energy Storage Materials is being developed to support the High Energy – High Capacity – High Performance High Cycle Battery Markets.

“Ultrathin Asymmetric Porous-Nickel Graphene-Based
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A New Generation Battery that is:

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Key Markets & Commercial Applications

 EV, (18650 & 21700); Drone and Marine Batteries
 Wearable Electronics and The Internet of Things
 Estimated $240B Market by 2037 

Batteries that Really Keep Going and Going and Going …

U of Waterloo: Forget the graphite-based lithium batteries currently powering your devices. Next-generation batteries could last for decades. Really.

With a potential lifespan of 10 to 20 years, Professor Zhongwei Chen’s next-generation rechargeable batteries are set to put the Energizer Bunny to shame.

“This battery could last 10 years, or even more than 20 years.”

Dr. Chen and his team are developing next-generation batteries and fuel cells. They are working on two types of batteries that are destined to be longer lasting and more efficient. One of these batteries is a rechargeable zinc battery that uses renewable energy, such as solar and wind. It could also be cost effective, which means that everyone could use it in the future.

Dr. Chen and his team are using novel materials to upgrade the traditional battery. He says that the key is to use silicon-based materials instead of graphite materials, which are currently being used in the commercial battery. Why? Silicon’s energy density is 10 times higher.

The result is a potential 150% energy density increase compared to its graphite-based lithium battery counterpart, which is currently being used to power electric cars and our cell phones. With the popularity of electric cars on the rise, companies such as Tesla and Panasonic are already looking to move beyond the limitations of the lithium battery.

Dr. Chen explains how he plans to solve the problems associated with the traditional battery as we move forward to meet the increased energy demands of the future.

MORE: Watch Our Current Battery Technology Project Video

A new company has been formed to exploit and commercialize the Next Generation Super-Capacitors and Batteries. The opportunity is based on Technology & Exclusive IP Licensing Rights from Rice University, discovered/ curated by Dr. James M. Tour, named “One of the Fifty (50) most influential scientists in the World today”

The Silicon Nanowires & Lithium Cobalt Oxide technology has been further advanced to provide a New Generation Battery that is:

 Energy Dense
 High Specific Power
 Affordable Cost
 Low Manufacturing Cost
 Rapid Charge/ Re-Charge
 Flexible Form Factor
 Long Warranty Life
 Non-Toxic
 Highly Scalable

Key Markets & Commercial Applications

 Motor Cycle/ EV Batteries
 Marine Batteries
 Drone Batteries and
 Power Banks
 Estimated $112B Market for Rechargeable Batteries by 2025