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Nano Focus: Applied voltage controls reversible mirror of gold plasmonic nanoparticles
25 Dec, 2017 | MRS BulletinFull Text External Link Indicator
Gold nanoparticles self-assemble to make efficient broadband plasmonic absorbers
08 Jul, 2016 | MRS BulletinFull Text External Link Indicator
"Plasmonic absorbers are gaining significant attention for applications such as photo/thermal detectors, solar energy conversion, and infrared imaging because of their exceptional ability to concentrate electromagnetic energy and trap it into thin layers to generate hot electrons. These absorbers are a determining factor in the performance of the whole system,
making their efficiency and bandwidth of absorption crucial. A research team from Nanjing University, China, has now fab-
ricated a broadband plasmonic absorber with average measured absorbance of 99% across wavelengths ranging from
400 nm to 10 μm." by Rachana Acharya
Research highlights: Perovskites
15 Mar, 2016 | MRS BulletinFull Text External Link Indicator
"Research on perovskites has progressed rapidly since the first perovskite-based solar cells with ~4% efficiency were reported in
2009. MRS Bulletin presents a selection of recent advances in this burgeoning field." by Prachi Patel
Photonic-crystal nanolasers shown to be highly sensitive biosensors
11 Jan, 2016 | MRS BulletinFull Text External Link Indicator
"Move over, ELISA. While the Enzyme-Linked ImmunoSorbent
Assay has long been one of the most popular ways of detecting and quantifying the presence of antibodies or antigens in solution, nanolasers may be poised to share the spotlight on the biosensor stage." by Rachel Berkowitz
Digital metamaterial bits for simpler optical elements
15 Dec, 2014 | MRS BulletinFull Text External Link Indicator
In this Information Age, digital electronics have become a crucial part of our everyday lives. Binary, or Boolean, logic has become ubiquitous in a society so closely affi liated with personal
electronics. The deceptively simple nature of the mathematical structure that uses 1s and 0s has enabled applications across a range of varied scientific fields.

In the September 14 issue of Nature Materials (DOI: 10.1038/NMAT4082), researchers at the University of Pennsylvania have proposed new methods of producing optical system designs
using digital metamaterial “bits” and “bytes.” Using simulations constructed with the COMSOL Multiphysics software, the researchers simulated the effective permittivity of two-component structures they label as metamaterial bytes; these were generated in both two-dimensional (2D) rectangular and concentric core–shell configurations. Each byte consisted of two bits, here comprising Ag and SiO2. It was seen that by altering factors such as bit order,
relative bit size, and orientation of the incident wave’s electric-field polarization, significant changes in the effective permittivity of the byte could be achieved. Additionally, permittivity values could be produced anywhere between the values of the two bits or even outside that range. Thus, it was demonstrated that, given the right conditions, a wide range of effective permittivity values could be produced from just two materials. Furthermore, the electromagnetic wave scattering from the digital bytes was found to be comparable to analogous homogenized structures." Ian McDonald
DOE announces $60M for solar power research
15 Jan, 2014 | MRS BullettinFull Text External Link Indicator
"Building on President Obama’s broad-based plan to cut carbon pollution and support clean energy innovation across the country, Energy Secretary Ernest Moniz announced in October 2013 about $60 million to support innovative solar-energy research and development. As part of the Department of Energy’s (DOE) SunShot Initiative, the purpose of these awards is to help lower the cost of solar electricity, advance
seamless grid integration, and support a growing US solar workforce."
NRC releases report on energy efficiency in autos by 2050
10 Jun, 2013 | MRS BulletinFull Text External Link Indicator
"The National Research Council finds that by the year 2050, the United States may be able to reduce petroleum consumption and greenhouse gas emissions by 80% for cars and small trucks through a combination of more efficient vehicles; the use of alternative fuels like biofuels, electricity, and hydrogen; and strong government policies to overcome high costs and influence consumer choices. While achieving these goals will be difficult, improving technologies driven by strong and effective policies could make deep reductions possible. The Council details its findings in the report, “Transitions to Alternative Vehicles and Fuels.”"
Nano Focus: High-capacity fiber-optic communications at the speed of light uses air as the medium
10 Jun, 2013 | MRS BulletinFull Text External Link Indicator
"Improving data transmission across computer networks is key to advancing the performance of modern data centers and massively parallelized supercomputers. Optical fibers provide outstanding transmission bandwidth, but light propagates 31% slower in a silica glass fiber than in vacuum, thus introducing a time delay. Air guidance in hollow-core fibers can improve this significantly, but it has proven challenging to achieve the combined values of loss, bandwidth and mode-coupling characteristics required for high-capacity data transmission.

Addressing this challenge, F. Poletti and colleagues from the University of Southampton have now fabricated hollow-core photonic-bandgap fibers (HC-PBGFs) that are capable of achieving both low surface scattering loss and wide surface-mode-free transmission bandwidth simultaneously (see Figure). This represents the first demonstration of fiber-based wavelength division multiplexed data transmission at close to (99.7%) the speed of light in a vacuum." Jean L. Njoroge
Nano Focus : Gold nanoparticles tailored to visualize fingerprints in reverse
10 Jun, 2013 | MRS BulletinFull Text External Link Indicator
"When forensic scientists attempt to visualize latent fingerprints, they typically rely on reagents that respond to amino acids or sebaceous materials. This type of visualization makes fingerprint ridges more apparent, but the quality of the print is highly reliant on the amount of residue left behind. As Sanaa Shenawi, Nimer Jaber, Joseph Almog, and Daniel Mandler from the Hebrew University of Jerusalem have reported in the May issue of Chemical Communications (DOI: 10.1039/c3cc41610k; p. 3688), fingerprints on paper can now be visualized with a chemical method that enhances the areas of the paper that are not covered by sebaceous matter. With this technique, the sebaceous material serves as a mask that protects the paper from the chemical reaction, and the prints appear as a “negative” or “reversed” image. According to Almog, “Despite the plethora of quite sophisticated fingerprint reagents that currently exist, there is still a need for more sensitive ones, since in criminal investigations, a considerable portion of the latent prints still escape detection.”" Anthony S. Stender
Theoretical Thermocrystals Control Heat Like Sound
29 Jan, 2013 | Materials360OnlineFull Text External Link Indicator
"Martin Maldovan of MIT has produced the theoretical framework that could make possible better control of heat flow in materials through the careful design of thermocrystals comprising alloys containing nanoparticles. This framework could lead to heat waveguides, heat lensing, thermal diodes, and thermal cloaking, among other long term potential applications." Tim Palucka

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