Carignano M.A.,Qatar Environment and Energy Research Institute
Journal of Physical Chemistry B | Year: 2013
Diethyl(methyl)(isobutyl)phosphonium hexafluorophosphate, [PF 6][P1,2,2,4], is an organic ionic plastic crystal with potential uses as a solid electrolyte in storage and light harvesting devices. In this work, we present a molecular dynamics simulation study for this material covering an extended temperature range, from 175 to 500 K. The simulations predict a transition from the crystalline to a semi plastic phase at 197 K, the onset of cation jump-like rotations at 280 K, a third transition at 340 K to a full plastic phase, and melting to 450 K. Overall, the simulations show a good agreement with the experimental findings, providing a wealth of detail in the structural and dynamic properties of the system. © 2013 American Chemical Society.
Ashhab S.,Qatar Environment and Energy Research Institute
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2014
We consider the Landau-Zener problem for a two-level system (or qubit) when this system interacts with one harmonic oscillator mode that is initially set to a finite-temperature thermal equilibrium state. The oscillator could represent an external mode that is strongly coupled to the qubit, e.g., an ionic oscillation mode in a molecule, or it could represent a prototypical uncontrolled environment. We analyze the qubit's occupation probabilities at the final time in a number of regimes, varying the qubit and oscillator frequencies, their coupling strength, and the temperature. In particular, we find a surprising nonmonotonic dependence on the coupling strength and temperature. © 2014 American Physical Society.
Berdiyorov G.R.,Qatar Environment and Energy Research Institute
Applied Surface Science | Year: 2015
MXenes are found to be promising electrode materials for energy storage applications. Recent theoretical and experimental studies indicate the possibility of using these novel low dimensional materials for metal-ion batteries. Herein, we use density-functional theory in combination with the nonequilibrium Green's function formalism to study the effect of lithium and sodium ion adsorption on the electronic transport properties of the MXene, Ti3C2. Oxygen, hydroxyl and fluorine terminated species are considered and the obtained results are compared with the ones for the pristine MXene. We found that the ion adsorption results in reduced electronic transport in the pristine MXene: Depending on the type of the ions and the bias voltage, the current in the system can be reduced by more than 30%. On the other hand, transport properties of the oxygen terminated sample can be improved by the ion adsorption: For both types of ions the current in the system can be increased by more than a factor of 4. However, the electronic transport is less affected by the ions in fluorinated and hydroxylated samples. These two samples show enhanced electronic transport as compared to the pristine MXene. The obtained results are explained in terms of electron localization in the system. © 2015 Elsevier B.V.
Ashhab S.,Qatar Environment and Energy Research Institute |
New Journal of Physics | Year: 2014
We propose possible approaches for the quantum simulation of itinerant spin-carrying particles in a superconducting qubit-resonator array. The standard Jaynes-Cummings-Hubbard setup considered in several recent studies can readily be used as a quantum simulator for a number of relevant phenomena, including the interaction with external magnetic fields and spin-orbit coupling. A more complex setup where multiple qubits and multiple resonator modes are utilized in the simulation gives a higher level of complexity, including the simulation of particles with high spin values, and it allows more direct control on processes related to spin-orbit coupling. This proposal could be implemented in state-of-the-art superconducting circuits in the near future. © 2014 IOP Publishing Ltd and Deutsche Physikalische Gesellschaft.
Georgescu I.M.,RIKEN |
Ashhab S.,RIKEN |
Ashhab S.,Qatar Environment and Energy Research Institute |
Nori F.,RIKEN |
And 2 more authors.
Reviews of Modern Physics | Year: 2014
Simulating quantum mechanics is known to be a difficult computational problem, especially when dealing with large systems. However, this difficulty may be overcome by using some controllable quantum system to study another less controllable or accessible quantum system, i.e., quantum simulation. Quantum simulation promises to have applications in the study of many problems in, e.g., condensed-matter physics, high-energy physics, atomic physics, quantum chemistry, and cosmology. Quantum simulation could be implemented using quantum computers, but also with simpler, analog devices that would require less control, and therefore, would be easier to construct. A number of quantum systems such as neutral atoms, ions, polar molecules, electrons in semiconductors, superconducting circuits, nuclear spins, and photons have been proposed as quantum simulators. This review outlines the main theoretical and experimental aspects of quantum simulation and emphasizes some of the challenges and promises of this fast-growing field. © 2014 American Physical Society.
News Article | October 10, 2016
Researchers at the National Institute of Information and Communications Technology, in collaboration with researchers at the Nippon Telegraph and Telephone Corporation and the Qatar Environment and Energy Research Institute have discovered qualitatively new states of a superconducting artificial atom dressed with virtual photons. The discovery was made using spectroscopic measurements on an artificial atom that is very strongly coupled to the light field inside a superconducting cavity. This result provides a new platform to investigate the interaction between light and matter at a fundamental level, helps understand quantum phase transitions and provides a route to applications of non-classical light such as Schrödinger cat states. It may contribute to the development of quantum technologies in areas such as quantum communication, quantum simulation and computation, or quantum metrology.
News Article | January 20, 2016
Abstract: EPFL scientists have developed a solar-panel material that can cut down on photovoltaic costs while achieving competitive power-conversion efficiency of 20.2%. Some of the most promising solar cells today use light-harvesting films made from perovskites - a group of materials that share a characteristic molecular structure. However, perovskite-based solar cells use expensive "hole-transporting" materials, whose function is to move the positive charges that are generated when light hits the perovskite film. Publishing in Nature Energy, EPFL scientists have now engineered a considerably cheaper hole-transporting material that costs only a fifth of existing ones while keeping the efficiency of the solar cell above 20%. As the quality of perovskite films increases, researchers are seeking other ways of improving the overall performance of solar cells. Inadvertently, this search targets the other key element of a solar panel, the hole-transporting layer, and specifically, the materials that make them up. There are currently only two hole-transporting materials available for perovskite-based solar cells. Both types are quite costly to synthesize, adding to the overall expense of the solar cell. To address this problem, a team of researchers led by Mohammad Nazeeruddin at EPFL developed a molecularly engineered hole-transporting material, called FDT, that can bring costs down while keeping efficiency up to competitive levels. Tests showed that the efficiency of FDT rose to 20.2% - higher than the other two, more expensive alternatives. And because FDT can be easily modified, it acts as a blueprint for an entire generation of new low-cost hole-transporting materials. "The best performing perovskite solar cells use hole transporting materials, which are difficult to make and purify, and are prohibitively expensive, costing over 300 per gram preventing market penetration," says Nazeeruddin. "By comparison, FDT is easy to synthesize and purify, and its cost is estimated to be a fifth of that for existing materials - while matching, and even surpassing their performance." ### This study was led by EPFL's Group for Molecular Engineering of Functional Materials, in collaboration with the Istituto di Scienze e Tecnologie Molecolari del Consiglio Nazionale delle Ricerche (Italy), Panasonic Corporation (Japan), EPFL's Laboratory for Photomolecular Science and Laboratory of Photonics and Interfaces, and the Qatar Environment and Energy Research Institute. It was funded by the European Union Seventh Framework Programme (MESO; ENERGY; NANOMATCELL), the Swiss National Science Foundation, and Nano-Tera. For more information, please click If you have a comment, please us. Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.
News Article | October 11, 2016
Researchers at the National Institute of Information and Communications Technology (NICT, President: Dr. Masao Sakauchi), in collaboration with researchers at the Nippon Telegraph and Telephone Corporation (NTT, Representative Member of the Board and President, Mr. Hiroo Unoura) and the Qatar Environment and Energy Research Institute (QEERI, Acting Executive Director: Dr. Marwan Khraisheh) have discovered qualitatively new states of a superconducting artificial atom dressed with virtual photons. The discovery was made using spectroscopic measurements on an artificial atom that is very strongly coupled to the light field inside a superconducting cavity. This result provides a new platform to investigate the interaction between light and matter at a fundamental level, helps understand quantum phase transitions and provides a route to applications of non-classical light such as Schrödinger cat states. It may contribute to the development of quantum technologies in areas such as quantum communication, quantum simulation and computation, or quantum metrology. This result will be published online in the October 10 (London time) issue of the journal Nature Physics. The indispensable technologies in modern life such as a time system measured by an atomic clock and a secure and energy-efficient communications system are based on the fundamental science of the interaction between light and matter at the single-photon level. The absorption and emission of light from any device is explained based on the interaction of light and atoms. A fundamental question in atomic physics, "How strong can the coupling of light and an atom be?" has not been answered in spite of years of research, because it is not easy to find appropriate methods to realize very strong coupling. It was predicted over forty years ago that if the coupling is extremely strong a qualitatively new lowest energy state (the ground state) of light and an atom should be realized. A debate soon started as to whether this prediction would still apply when realistic conditions are considered. A few years ago, our collaborator at QEERI, Dr. Sahel Ashhab, performed theoretical investigations and identified desirable conditions for achieving this new state using superconducting circuits. In the experiment, we used a microfabricated superconducting harmonic oscillator and a superconducting artificial atom (quantum bit or qubit) whose electronic states behave quantum mechanically, just like a natural atom. By carefully designing a superconducting persistent-current qubit interacting with an LC harmonic oscillator that has a large zero-point fluctuation current via a large shared Josephson inductance, we found the new ground state as predicted theoretically. The total energy of the qubit and the oscillator is the sum of the photon energy in the oscillator, the qubit energy, and the coupling energy binding the photons to the qubit. Taking advantage of the macroscopic quantum system, we could realize circuits with coupling energy larger than both the photon energy and the qubit energy. This situation is sometimes called 'deep strong coupling'. In addition, we have observed that the transitions between energy levels are governed by selection rules stemming from the symmetry of the entangled energy eigenstates, including the ground state. We plan to test whether deep strong coupling is possible or not using more than one superconducting artificial atom (qubit), which remains a question of debate. We will also try to actively manipulate this new molecular state of photons and artificial atoms, for example, to observe and control the dynamics of photon absorption and emission, and to demonstrate new methods of entanglement generation.
News Article | January 20, 2016
École Polytechnique Fédérale de Lausanne (EPFL) scientists have developed a solar-panel material that can cut down on photovoltaic costs while achieving competitive power-conversion efficiency of 20.2 percent. Some of the most promising solar cells today use light-harvesting films made from perovskites — a group of materials that share a characteristic molecular structure. However, perovskite-based solar cells use expensive “hole-transporting” materials, whose function is to move the positive charges that are generated when light hits the perovskite film. Publishing in Nature Energy, EPFL scientists have now engineered a considerably cheaper hole-transporting material that costs only a fifth of existing ones while keeping the efficiency of the solar cell above 20 percent. As the quality of perovskite films increases, researchers are seeking other ways of improving the overall performance of solar cells. Inadvertently, this search targets the other key element of a solar panel, the hole-transporting layer, and specifically, the materials that make them up. There are currently only two hole-transporting materials available for perovskite-based solar cells. Both types are quite costly to synthesize, adding to the overall expense of the solar cell. To address this problem, a team of researchers led by Mohammad Nazeeruddin at EPFL developed a molecularly engineered hole-transporting material called FDT that can bring costs down while keeping efficiency up to competitive levels. Tests showed that the efficiency of FDT rose to 20.2 percent — higher than the other two, more expensive alternatives. And because FDT can be easily modified, it acts as a blueprint for an entire generation of new low-cost hole-transporting materials. “The best performing perovskite solar cells use hole transporting materials, which are difficult to make and purify and are prohibitively expensive, costing [over $300] per gram, preventing market penetration,” says Nazeeruddin. “By comparison, FDT is easy to synthesize and purify, and its cost is estimated to be a fifth of that for existing materials — while matching, and even surpassing their performance.” This study was led by EPFL’s Group for Molecular Engineering of Functional Materials, in collaboration with the Istituto di Scienze e Tecnologie Molecolari del Consiglio Nazionale delle Ricerche (Italy), Panasonic Corporation (Japan), EPFL’s Laboratory for Photomolecular Science and Laboratory of Photonics and Interfaces, and the Qatar Environment and Energy Research Institute. It was funded by the European Union Seventh Framework Programme (MESO; ENERGY; NANOMATCELL), the Swiss National Science Foundation, and Nano-Tera. Release Date: January 18, 2016 Source: École Polytechnique Fédérale de Lausanne
News Article | August 31, 2016
In 2008, Joel Malek, a DNA-sequencing specialist from Boston, Massachusetts, packed his bags and left one east coast for another, 6,500 miles away in Qatar. At the time, the Arab state was recruiting skilled scientists and academics to teach and conduct research in its 14-square-kilometre 'Education City', which was under construction on the outskirts of Doha. Malek was given generous funding to set up a genomics research lab for Weill Cornell Medicine-Qatar (WCM-Q), the first US medical school to open a campus in the country, in 2001. Eight months after settling on the peninsula's shores, Malek received funding and began building his research team almost from scratch. Three years later, he published a draft genome of a date palm (Phoenix dactylifera) ( et al. Nature Biotechnol. 29, 521–527; 2011). Malek's work made it possible to determine the sex of the economically important crop at the seed stage, rather than waiting until the tree was five years old — a significant discovery because only females bear fruit. As well as Weill Cornell, there are seven other US and European universities in Qatar. “Those universities came to Qatar because the country wanted to move very quickly into the future,” explains Laith Abu-Raddad, a public-health specialist at WCM-Q. “One way to do it was to bring the best universities in the world into Qatar and ensure that they have the same quality and standards as the home institutions,” he says. The embrace of science in the Gulf states is motivated by near- and long-term concerns. The drop in oil prices that began in June 2014 put all of the Gulf economies “in a state of shock”, says chemical engineer Steve Griffiths, vice-president for research at Masdar Institute in Abu Dhabi. Although oil prices are on a timid upward trend, the sharp loss in revenues has steered finances towards other sources of income. And there's little question that, as oil supplies dwindle, these countries will need a new engine to drive their prosperity. Every year, the Qatar Foundation for Education, Science and Community Development reportedly allocates US$320 million to run six campuses of US universities. The foundation, created in 1995 by then emir Sheikh Hamad bin Khalifa Al Thani and his wife Sheikha Moza bint Nasser, is a non-profit organization that receives both private and government support. Tasked with paying for research and designing the country's science policy, the foundation established the Qatar National Research Fund (QNRF) in 2006. The QNRF awards money for research within the four national-priority sectors: energy and the environment; computer sciences and information technologies; health and life sciences; and social sciences, arts and the humanities. In May 2012, QNRF granted $4.5 million to Malek's date-palm research as part of its National Priorities Research Program. QNRF is still “a nascent organization”, according to executive director Abdul Sattar Al-Taie. In its first stage, he says, it was focused on creating and nurturing a research culture in Qatar by providing training, creating career opportunities and bolstering the workforce with experienced scientists. “There will be many challenges to overcome before we can say that the country's investment in this area can absorb the government's full commitment,” says Al-Taie. Its second phase, which started in 2011, focuses on mission-driven research that addresses Qatar's grand challenges — health care and water, and cyber and energy security — to ultimately create tangible knowledge assets such as intellectual property, Al-Taie says. The QNRF has also funded research projects that led to the discovery of five exoplanets that bear the country's name (Qatar-1b to Qatar-5b), as well as a collaboration with CERN, Europe's particle-physics laboratory, to upgrade the Large Hadron Collider. On a less cosmic scale, the foundation has also funded research at the Qatar Environment and Energy Research Institute on novel excitonic materials to boost the energy, harvesting capacity of solar cells. Elsewhere in the Gulf region, the United Arab Emirates (UAE) and Saudi Arabia are also striving to give an octane boost to their research and development (R&D) enterprises. In 2002, Saudi Arabia, the world's largest oil exporter, introduced the National Science, Technology and Innovation Plan (NSTIP), the government's long-term strategy for scientific advancement. As part of the first phase, which ran from 2008 to 2014, 7 billion Saudi Arabian riyal (US$1.9 billion) was allocated to R&D to help establish the kingdom as a regional science powerhouse. Those efforts are starting to pay off. In 2016, Nature Index, which tracks the quality and quantity of scientific publications in top journals by institutions all over the world, ranked Saudi Arabia as the most prolific producer of high-quality research in the Arab world, and second only to Israel in western Asia. The NSTIP is implemented by the King Abdulaziz City for Science and Technology (KACST), which is charged with funding academic science at institutions throughout the kingdom. KACST's research budget in the National Transformation Program (NTP) for the next 5 years comes to $8.3 billion. Among the projects supported by KACST is the Saudi Human Genome Program, which seeks to identify the genes responsible for genetic diseases by sequencing the genomes of 100,000 Saudi participants. KACST also has its own research laboratories, says Anas Alfaris, a KACST faculty member who chairs the task force handling the R&D strategy in the NTP. Another major Saudi research project is the construction of the world's first large-scale, solar-powered desalination facility. It will be located in Al Khafji, near the Kuwait border. Advanced Water Technology, an arm of KACST, and the Spanish company Abengoa agreed to jointly build the plant, which is estimated to cost $130 million and is expected to be completed by early 2017. It will supply 60,000 cubic metres of desalinated sea water a day. Research funding is proceeding along two tracks, says Alfaris. The first includes funding fields in which the country could become a global leader — oil and gas, solar energy, water desalination and advanced materials. The second, Alfaris says, involves funding areas in which “we believe the kingdom needs to be fairly self-reliant”, such as health, agriculture, food research, transportation, construction and information technology. Given that Saudi Arabia still derives 80% of its budget revenue and 90% of its export earnings from the petroleum sector, it's not surprising that two-thirds of papers published in high-impact journals by Saudi researchers focus on chemistry. Researchers at the King Abdullah University of Science and Technology (KAUST), for example, are studying energy-efficient membranes for water desalination and developing metal–organic materials to offer clean-energy alternatives, reduce greenhouse-gas emissions and remediate chemical and biological agents. The UAE has the most diversified economy of the region. Dubai especially so, because it does not have bountiful natural resources like the adjacent state of Abu Dhabi. Dubai started investing in logistics, airline and port infrastructure in the 1970s. In 2012, R&D expenditure represented 0.5% of the gross domestic product (GDP). That year the Ministry of Higher Education and Scientific Research announced a target of 1.5% of GDP by 2021. “Science is an essential component of the economic diversification in the UAE; it will establish a robust base for R&D in crucial sectors such as aerospace, defence, energy, water, mining, space, health care, renewable energy, information technology and education,” says Griffiths. The Masdar Institute, where researchers are working on alternative energy, environmental sustainability and clean technology, is emblematic of Abu Dhabi's efforts to broaden its economy in preparation for a post-oil age. Griffiths says that the institute's satellite data are used by Etihad Airways, Abu Dhabi's national airline, to predict periods of fog that impede air traffic, and its expertise in the area will be used as part of the UAE's space programme. Masdar has about 25 R&D collaborations with UAE companies and an equal number with international organizations, Griffiths says, in fields including energy, water, logistics, aerospace and defence, metals and mining, and semiconductors. “Large streams of revenues have been steered towards sectors where competition is not based on oil and gas,” he says. Christian Henderson, who is researching the political economy of Saudi Arabia at the SOAS University of London, explains that the strategies that were put in place to diversify the Gulf economies occurred at a time when oil was priced at $100 a barrel (twice as high as in 2016), and money to invest in massive R&D projects was plentiful. The Gulf countries “would like to spend money on R&D but I don't see any kind of diversification of the economy, in the sense of establishing industries that are not reliant on government funds and viable on a free-market level”, Henderson says. The best gauge of diversification is the percentage of the budget derived from oil revenue, he says, which, in many of these states, is still “80–90% of the budget”. With the current low price of oil, countries in the region are seeking investments with a clear near-term return. Ironically, given that the long-term goal of research for the Gulf states is to free themselves from oil dependence, the drop in the oil price has reduced the amount of money available to fund science. According to Sami Mahroum, director of the Innovation and Policy Initiative at the graduate business school INSEAD in Abu Dhabi, this tightening may be temporary. “The UAE and other Gulf countries do not expect to replace oil revenues with the commercialization of science — they are not that naive,” he says. The aim is merely for “knowledge-intensive products to represent a greater share of the GDP”. The UAE is investing in aerospace, semiconductors, health and energy to become, according to Mahroum, an integral part of these sectors globally, without being fully independent of what is happening around the world. Mahroum thinks that although the UAE's economic diversification is more accomplished than that of other countries in the region, innovation is mostly Internet-driven and not triggered by R&D. Few successful companies have emerged from academic research, he says. The reason for this is structural. The economy is dominated by large, state-owned companies and by conglomerates run by influential families. Unless these big organizations decide to embark on large-scale R&D, Mahroum contends, science won't be the driver of economic diversification in the UAE or across the region. “Science and technology cannot be undertaken by start-ups that do not have the resources to invest in state-of-the-art labs, and cannot afford to wait for a decade for their product to be commercialized,” he says. Despite the current lack of research commercialization, Mahroum is sure that R&D will have a bigger role in the economy in the not too distant future, especially in areas such as energy, water, agriculture and health. “Those areas are in strong demand and high on the policy agenda, and have already a strong presence in local universities,” he explains. The introduction of legislation to liberalize the market and break monopolies in certain areas would encourage investments in science, Mahroum says. “It would drive more people to be trained in science and technology, and that as a consequence, the scientific output of the region would increase significantly.”