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Menlo Park, CA, United States

The Stanford Synchrotron Radiation Lightsource , a division of SLAC National Accelerator Laboratory, is operated by Stanford University for the Department of Energy. SSRL is a National User Facility which provides synchrotron radiation, a name given to electromagnetic radiation in the x-ray, ultraviolet, visible and infrared realms produced by electrons circulating in a storage ring at nearly the speed of light. The extremely bright light that is produced can be used to investigate various forms of matter ranging from objects of atomic and molecular size to man-made materials with unusual properties. The obtained information and knowledge is of great value to society, with impact in areas such as the environment, future technologies, health, and education.The SSRL provides experimental facilities to some 2,000 academic and industrial scientists working in such varied fields as drug design, environmental cleanup, electronics, and x-ray imaging. It is located in southern San Mateo County, just outside the city of Menlo Park. Wikipedia.

Brongersma M.L.,Stanford University | Cui Y.,Stanford University | Cui Y.,SLAC | Fan S.,Stanford University
Nature Materials

High-performance photovoltaic cells use semiconductors to convert sunlight into clean electrical power, and transparent dielectrics or conductive oxides as antireflection coatings. A common feature of these materials is their high refractive index. Whereas high-index materials in a planar form tend to produce a strong, undesired reflection of sunlight, high-index nanostructures afford new ways to manipulate light at a subwavelength scale. For example, nanoscale wires, particles and voids support strong optical resonances that can enhance and effectively control light absorption and scattering processes. As such, they provide ideal building blocks for novel, broadband antireflection coatings, light-trapping layers and super-absorbing films. This Review discusses some of the recent developments in the design and implementation of such photonic elements in thin-film photovoltaic cells. © 2014 Macmillan Publishers Limited. Source

Luntz A.C.,SLAC | McCloskey B.D.,University of California at Berkeley | McCloskey B.D.,Lawrence Berkeley National Laboratory
Chemical Reviews

The major issue confronting complete electrification of road transport is simply a battery problem. While both metrics are undoubtedly important, which of the two is the most important for EV applications is somewhat debated, even among the different EV manufacturers. Traditional car companies emphasize more the importance of energy density, while Tesla emphasizes more the specific energy since they tend to design a car around the battery pack. The history of rechargeable non-aqueous Li-air batteries at this stage is so short that the field must be considered a work in progress. In fact, even the basic mechanisms and rationale for many of the fundamental properties of Li-air are still in dispute among many of the researchers in the field. Source

Atomic resolution structures of large biomacromolecular complexes can now be recorded at room temperature from crystals with submicrometer dimensions using intense femtosecond pulses delivered by the worlds largest and most powerful X-ray machine, a laser called the Linac Coherent Light Source. Abundant opportunities exist for the bioanalytical sciences to help extend this revolutionary advance in structural biology to the ultimate goal of recording molecular-movies of noncrystalline biomacromolecules. This Feature will introduce the concept of serial femtosecond crystallography to the nonexpert, briefly review progress to date, and highlight some potential contributions from the analytical sciences. © 2013 American Chemical Society. Source

Rizzo T.G.,SLAC
Physical Review D - Particles, Fields, Gravitation and Cosmology

The E 6SSM extension of the minimal supersymmetric standard model allows for the solution of many of the difficulties that are usually encountered within conventional supersymmetry-breaking scenarios, e.g., the μ problem, the imposition of R-parity "by hand," the generation of light neutrino masses and obtaining a light Higgs boson with a mass as large as ∼125GeV as suggested by recent LHC measurements. In addressing these problems, such a scenario predicts the existence of additional singlet and vectorlike superfields beyond those in the minimal supersymmetric standard model as well as possibly two new neutral gauge bosons near the TeV scale. In this paper the phenomenological implications of simultaneous gauge kinetic mixing between the usual standard model hypercharge gauge field and both these new neutral gauge fields present in the E 6SSM scenario is explored. To this end a large class of specific toy models realizing this type of kinetic mixing is examined. In particular, we demonstrate that a significant suppression (or enhancement) of the expected event rate for Z ′ production in the dilepton channel at the LHC is not likely to occur in this scenario due to gauge kinetic mixing. © 2012 American Physical Society. Source

Mannsfeld S.C.B.,SLAC
Nature Materials

Stefan C. B. Mannsfeld states that development in organic electronics depends on the understanding of the structure-property relationships of organic materials. Resonant scattering of polarized soft X-rays (P-SoXS) by aromatic carbon bonds has been used to probe molecular orientation in thin organic semiconductor films down to length scales of 20 nm. The basic principle of the P-SoXS technique involves a polarized soft X-ray beam passing through a thin sample and the scattering signal and recorded by an X-ray sensitive detector. Soft X-rays are distinguished from hard X-rays by their lower photon energies, which fall into the same energy range as the fundamental electronic transitions of many lighter atoms, including carbon. The novelty of P-SoXS lies in the use of scattering with polarized soft X-rays whose energy is tuned to a fundamental carbon transition in aromatic carbon ring systems. Source

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