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Jiayi Shi, Taiwan

The Intelligence Advanced Research Projects Activity (IARPA) invests in high-risk, high-payoff research programs to tackle some of the most difficult challenges in the intelligence community. One of these challenges is dealing with encryption. Codes considered unbreakable by today's best supercomputers could be handled in a matter of hours by quantum computers. The basic building blocks of a quantum device are qubits. These are the quantum mechanical analogue of a traditional logical bit, which can be in a "1" or a "0" state. Quantum physics allows for qubits to take on multiple configurations simultaneously (e.g. an equally-weighted superposition of 0 and 1), which is forbidden in conventional computing. When scientists in the 1990s proved that this strange property could be harnessed for solving certain tasks, such as decryption, the quantum information revolution began. While researchers have proven that robust qubits can be built, scaling them into large networks while detecting and correcting errors remains a challenge. IARPA has selected the Duke/Maryland/Georgia Tech partnership as one of the awardees in its program dubbed LogiQ. Their goal is to bring together a large number of atomic qubits to realize modular "super-qubits" that can be scaled up while correcting for errors. This major multi-year award is led by Jungsang Kim (Duke University), Christopher Monroe (University of Maryland and the Joint Quantum Institute) and Ken Brown (Georgia Tech). The effort also includes industry partners AOSense, Inc. (Sunnyvale, California), ColdQuanta, Inc. (Boulder, Colorado) and Harris Corporation (Melbourne, Florida), as well as theoretical support from Andrew Childs (University of Maryland and the Joint Center for Quantum Information and Computer Science) and Luming Duan (University of Michigan). "Our ion trapping approach is one of the leading technologies that can accomplish this goal," said Jungsang Kim, professor of electrical and computer engineering, computer science, and physics at Duke University, and the principal investigator on the project. "We're excited that IARPA sees our group as one of the leaders in the field and has entrusted this important task to us." Quantum systems are fundamentally delicate, and superpositions collapse if they are observed. In other words, before useful information can be extracted, computational resources can be compromised and even destroyed by interactions with the environment. But this obstacle is not insurmountable. One of the first steps is to construct an extremely robust physical realization of a qubit. In this regard, physicists have demonstrated that trapped atomic ions have quantum staying power. In this system, each qubit is stored in the internal energy levels of a single atomic ion—the same states that are used in atomic clocks. Such states boast coherence times unmatched in any other physical system. The qubits are manipulated through laser and microwave radiation to form quantum logic gates and extended circuits for calculations. Ion trappers have become quite adept at controlling a handful of individual qubits. This collaboration has previously proposed and performed demonstrations that their approach is scalable and modular, a necessity because many qubits are needed for useful quantum computation. "Atomic ion qubits are fundamentally scalable, because they can be replicated with virtually identical characteristics: an isolated ytterbium atom is exactly the same in Washington, D.C. as it is in Los Angeles," said Christopher Monroe, professor of physics at the University of Maryland and the Joint Quantum Institute, and co-leader on the project. "Quantum computing is going through the same research and design processes that conventional computing went through decades ago," said Kim. "Just as the first digital computer was constructed once we had reliable switching devices, we are ready to explore the construction of more complex quantum circuits based on the robust multi-qubit manipulation that is possible in trapped ions." But all potential quantum computing technologies still face the same problem that is central to the new IARPA LogiQ program: quantum error correction. "We know how to build a quantum computer with 50-100 qubits with trapped ions right now," said Monroe. "This is a big enough system that we cannot simulate what happens, even with all the conventional computers in the world. But some killer applications of quantum computing require thousands or millions of qubits, and error correction will be crucial to getting there." As with a conventional computer, scientists can encode quantum systems in a way that corrects for errors that happen along the way, such as an accidental bit flip where a 1 becomes 0, or vice versa. Even in record-breaking pristine ion-trapping systems, errors grow fairly rapidly as qubits are added. Because of that sneaky rule that makes quantum systems collapse due to measurement—intentional or otherwise—simply interrogating the qubits directly and fixing the broken ones destroys the quantum computation. The idea of a modular super-qubit or logical qubit begins to address this problem. In this system, the information stored in a logical qubit is encoded into specialized quantum states comprising multiple physical qubits. Distributing the information in this way not only adds protection—it allows for errors to be detected and corrected, all without actually knowing (or needing to know) the exact details of the quantum state as a whole. "The engineering required to achieve the goal of stopping qubits from degrading through error correction will go a long way toward making quantum computers practically viable," said Kim. Explore further: Researchers find qubits based on trapped ions offer a promising scalable platform for quantum computing


Improving batteries' performance is key to the development and success of many much-hyped technologies, from solar and wind energy to electric cars. They need to hold more energy, last longer, be cheaper and safer. Research into how to achieve that has followed several avenues, from using different materials than the existing lithium-ion batteries to changing the internal structure of batteries using nanoparticles—parts so small they are invisible to the naked eye. Nanotechnology can increase the size and surface of batteries electrodes, the rods inside the batteries that absorb the energy. It does so by effectively making the electrodes sponge-like, so that they can absorb more energy during charging and ultimately increasing the energy storage capacity. Prague-based company HE3DA has developed such a technology by using the nanotechnology to move from the current flat electrodes to make them three dimensional. With prototypes undergoing successful testing, it hopes to have the battery on the market at the end of this year. "In the future, this will be the mainstream," said Jan Prochazka, the president. He said it would be targeted at high-intensity industries like automobiles and the energy sector, rather than mobile phones, because that is where it can make the biggest difference through its use of his bigger electrodes. In combination with an internal cooling system the batteries, which are being tested now, should be safe from overheating or exploding, a major concern with existing technologies. Researchers at the University of Michigan and MIT have likewise focused on nanotechnology to improve the existing lithium-ion technology. Others have sought to use different materials. One of the most promising is lithium oxygen, which theoretically could store five to 10 times the energy of a lithium ion battery, but there have been a number of technical problems that made it inefficient. Batteries based on sodium-ion, aluminium-air and aluminium-graphite are also being explored. There's even research on a battery powered by urine. Tesla Motors has been building a $5 billion "gigafactory" to produce lithium-ion batteries for use in its electric cars and potentially to store electricity for homes. It is not using any new technologies, however, just producing very large battery units and marketing them for new purposes. More efficient batteries are crucial if cars are to increase their driving range, which is currently limited compared with what fossil fuels can provide. In renewable energy, powerful batteries are needed to store the energy created by solar panels or wind farms, which gets dispersed when it is sent for long distances. George Crabtree, a Distinguished Fellow at the Argonne National Laboratory in the United States and director of the Joint Center for Energy Storage Research, called the nanotechnology model "a very interesting battery." "There's no doubt that increasing the size of the electrodes that is making them 3D instead of 2D would be a big step forward. That is actually a very right target for advancing lithium ion batteries," he said. "The energy is stored in the electrode, so if you can make the electrodes bigger, say 10 times bigger, then you can have 10 times the amount of energy stored on one charge." Prochazka's battery company is among a group of Czech nanotechnology companies that are gaining international interest. A production facility of HE3DA will be financed by a Chinese investor with an initial investment of almost 1.5 billion koruna ($62 million) that is forecast to double. Explore further: New cathode material creates possibilities for sodium-ion batteries


News Article | August 30, 2016
Site: www.fastcompany.com

Pay equity is about more than just gender equality at work. Violence against women also plays a role in the wage gap, according to a report from McKinsey & Company. The Power of Parity: Advancing Women’s Equality in the United States, finds that closing the wage gap could add up to $4.3 trillion annually to the GDP by 2025. But violence against women is one of the six factors impacting pay equity in the United States. Fast Company covered some of the other factors working against pay parity for women from the report. They included lack of representation in leadership and managerial positions (there are 66 women for every 100 men in managerial positions), time spent in unpaid care work (women do almost twice the amount of unpaid care work), single mothers (60% of families living in poverty are led by a single mother), teenage pregnancy (600,000 girls ages 16 to 19 become pregnant each year) and political representation (there are 30 women in every 100 men in political office). "There is a direct correlation between violence and the financial piece," says Vivian Riefberg, a senior partner at McKinsey & Company and one of the report’s authors. "Women who suffer violence are likely to see an impact on their earning potential due to lost productivity and lost work days." This is more common than you may know. As many as one in three women experience violence from an intimate partner, the report found. And there is one incident of sexual violence (not just rape, but all forms of violence) for every two women. Using data from a CDC report, McKinsey’s analysts calculated that violence against women costs about $4.9 billion in the United States annually. Seventy percent of this comes from direct medical costs, 15% from lost productivity, and 15% from lost earnings over women’s lifetimes. Victims of domestic violence have missed opportunities for promotions and pay raises because it appears they have performance issues, she says. "We hear from women on a regular basis that domestic violence prevents them from going into work," says Katie Ray-Jones, CEO of the National Domestic Violence Hotline. It is not uncommon for the abuser to make the victim appear unreliable in the workplace, says Lisalyn R. Jacobs, CEO of Just Solutions. That’s because one way an abuser is able to control the victim is through their finances. For instance, she says, the abuser might promise to take the kids to school in the morning, but then say they can’t. Or, they might commit an act of violence the day before an important meeting or an interview. They might show up at the victim’s workplace or keep calling her there and harass her or her colleagues. "They will commit any type of behavior that causes an employer to do a cost-benefit analysis around whether to keep you employed," says Jacobs. "This can have an effect on employment history and whether someone gets promoted or is eligible for a raise." A woman with a black eye or bruises in a visible place is more likely to call in sick, rather explain what happened, says Ellen Bravo, director of Family Values @ Work, an organization that advocates for paid family leave and sick leave. This is particularly true, she says, if the woman has experienced repeated violence and has made up multiple excuses like being in a car accident or falling down the stairs. "In most cases," says Bravo, "your employer will see you as a unreliable employee, rather than someone who is being abused." Victims of domestic violence also risk job loss, says Dina Bakst, cofounder and copresident of A Better Balance, a national legal advocacy organization that advocates for family-friendly laws and workplace policies. Between 25% and 50% of domestic violence survivors report job loss, due at least in part to the domestic violence, according to research from the Joint Center for Poverty Research at Northwestern University. Once you lose one job, it’s harder to get a new job. If you lose two jobs, it becomes increasingly harder to find employment which exacerbates the wage gap, Bakst says. To help level the playing field, A Better Balance is working with cities, counties, and states to pass legislation that would give victims of domestic violence paid "safe time." Paid safe time is necessary because it takes time to deal with the legal and medical issues resulting from domestic violence such as going to court, finding and moving to a new home, and seeing a counselor. Bravo points out that it typically takes three hours to file the paperwork to get an injunction against an abuser. Courthouse employees say it’s not uncommon for a woman come in, start the process, then realize they need to go back to work or risk losing their jobs, she adds. To date, five states (California, Connecticut, Massachusetts, Oregon, and Vermont), 10 localities (Montgomery County, Maryland; Seattle, San Diego, Tacoma, Washington; Spokane, Washington; Santa Monica, California; Minneapolis, Los Angeles, Chicago, Philadelphia, and Washington, D.C.) have passed safe time laws, says Jared Make, senior staff attorney at A Better Balance. In addition, San Francisco is in the process of adding safe time to its paid sick leave law. The provision is expected to be in place in 2017. Although California has a statewide safe time law, California cities are passing their own laws to provide added protections, Make says. This comparison chart outlines state laws regarding paid time off for sick and safe time leave. Meanwhile Washington state, Arizona, and the city of Albuquerque, New Mexico, are asking voters to decide this November whether to provide paid safe time, and St. Paul, Minnesota, is working on a legislative initiative to provide paid safe time, Make says. Advocates for domestic violence victims say rather than automatically firing an employee who appears unreliable, managers should take time to find out what’s going on. Here are five signs to look for, according to the National Domestic Violence Hotline: An employee who is showing not just one, but all of these signs, could be experiencing abuse at home, Ray-Jones says. To accommodate victims of domestic violence, employers could consider changing their phone number, moving their desk away from a window or public area, putting a lock on the employee’s office door, and having a policy in place that protects victims of violence, says Kiersten Stewart, director of public policy and advocacy at Futures Without Violence. "Know the warning signs," Bravo advises employers, "and make it a safe place for someone to tell the right person, ‘I’m in trouble and it may affect my attendance and performance and it’s not because I’m not a good employee.’"


News Article | March 31, 2016
Site: phys.org

Ever worry that your cell phone will fade when you need it most? Or that the same thing will happen when driving your electric car? Lightweight lithium-sulfur batteries could be the answer, holding two times the energy of those on store shelves, but they often fade and won't hold a charge for long. Through the Joint Center for Energy Storage Research (JCESR), scientists at DOE's Pacific Northwest National Laboratory identified one of the reasons behind this problem.


Crystalline silicon solar cells make up the majority of solar panels out in the world today, but scientists believe that other types have the potential to be more efficient and carry more benefits. One of those types is perovskite solar cells, called that because they are made from compounds that have the crystal structure of the mineral perovskite. These solar cells are inexpensive and easy to fabricate, making them a great alternative to traditional solar cells. Scientists have been working with this technology for about seven years and in just that amount of time the efficiency of those cells has increased from just three percent in 2009 to 22 percent today -- similar to silicon solar cells. That's the fastest efficiency increase of any solar cell material so far. Scientists at the Berkeley Lab's Molecular Foundry and the Joint Center for Artificial Photosynthesis have made a discovery that could push that efficiency up even higher -- up to 31 percent. Using photoconductive atomic force microscopy to study the structures of the cells at the nanoscale level, the researchers were able to map photocurrent generation and open circuit voltage in the active layer of the solar cell -- two properties that affect the conversion efficiency. The maps revealed a surface composed of bumpy, gemstone-like grains measuring about 200 nanometers each. Each grain had multiple facets that it turns out had varying conversion efficiencies. Some facets of the grains were highly efficient, reaching the 31 percent mark, while others were much lower. The researchers believe that if they can study the high efficiency facets and understand what makes them better at converting sunlight to electricity, they can produce a much higher efficiency solar cell overall. “If the material can be synthesized so that only very efficient facets develop, then we could see a big jump in the efficiency of perovskite solar cells, possibly approaching 31 percent,” said Sibel Leblebici, a postdoctoral researcher at the Molecular Foundry. The researchers found that each of the facets behaved like tiny solar cells all connected in parallel -- some performing really well and others not so much. The current flows towards the poorly-performing facets, which lowers the performance of the entire solar material. They believe that if the material could be constructed so that only the high efficiency facets connect with the electrode, then the efficiency of the solar cell would jump to as high as 31 percent, leading to a higher-performing and less expensive solar material than we use today.

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