01. Speed of light drops to zero at ‘exceptional points’ 02. Compound could transform energy storage for large grids 03. Researchers demonstrate graphene as a source of high-speed light pulses 04. Innovative diode design uses ultrafast quantum tunneling to harvest infrared energy from the environment 05. A fast-evolving new botnet could take gadgets in your home to the dark side 06. Clemson researchers blaze new ground in wireless energy generation 07. Vanadium dioxyde: A revolutionary material for tomorrow’s electronics 08. Controlling quantum interactions in a single material 09. Certain bacteria produce tiny gold nuggets by digesting toxic metals 10. The […]
Certain bacteria produce tiny gold nuggets by digesting toxic metals
Science Daily January 31, 2018 In nature, C. metallidurans plays a key role in the formation of so-called secondary gold, which emerges following the breakdown of primary, geologically created, ancient gold ores. It transforms the toxic gold particles formed by the weathering process into harmless gold particles, thereby producing gold nuggets only a few nanometers in size. An international team of researchers (Germany, Australia) has discovered the molecular processes that take place inside the bacteria C. metallidurans to extract valuable trace elements, including tiny gold nuggets, without poisoning itself… read more. TECHNICAL ARTICLE
Innovative diode design uses ultrafast quantum tunneling to harvest infrared energy from the environment
Phys org February 5, 2018 Researchers in Saudi Arabia have designed a device, rectenna, that can tap into the infrared radiation in the environment and waste heat from industrial processes and transform quadrillionth-of-a-second wave signals into useful electricity. Tunneling devices, such as metal-insulator-metal (MIM) diodes, rectify infrared waves into current by moving electrons through a small barrier. They used a ‘bowtie-shaped’ nano-antenna that sandwiches the thin insulator film between two slightly overlapped metallic arms to generate the intense fields needed for tunneling… read more.
Researchers demonstrate graphene as a source of high-speed light pulses
Phys org February 5, 2018 An international team of researchers (South Korea, USA – Columbia University, MIT, Cornell University, Stanford University, SLAC, University of Minnesota, Spain, Japan) encapsulated graphene in hexagonal boron nitride which allows the graphene to reach temperatures that are high enough to emit bright light in the visible and near infrared range, with good stability (estimated device lifetimes of at least 4 years), and fast cooling. As a result, the device generates ultrafast light pulses with a duration as short as 90 picoseconds and a modulation rate that is several orders of magnitude faster than conventional thermal […]
Compound could transform energy storage for large grids
Phys org February 5, 2018 A team of researchers in the US (University of Rochester, State University of New York – Buffalo) developed a method to modify polyoxometalates by replacing the compound’s methanol-derived methoxide groups with ethanol-based ethoxide ligands. They expanded the potential window during which the cluster was stable, doubling the amount of electrical energy that could be stored in the battery. The ethoxide and methoxide clusters can be generated by using methanol and ethanol. Both reagents are inexpensive, readily available and safe to use. According to the researchers the process may set a new standard in the field… […]
Clemson researchers blaze new ground in wireless energy generation
EurekAlert February 5, 2018 Researchers at Clemson University have invented a wireless triboelectric nanogenerator (W-TENG) based on their earlier invention U-TENG. W-TENG is made of a multipart fiber, made of graphene and poly-lactic acid, and Teflon. The device generates a max voltage of 3000 volts – enough to power 25 standard electrical outlets. Because the voltage is so high, the W-TENG generates an electric field around itself that can be sensed wirelessly. Its electrical energy can be stored wirelessly in capacitors and batteries. According to the researchers the device has applications in outer space, the middle of the ocean or […]
Vanadium dioxyde: A revolutionary material for tomorrow’s electronics
EurekAlert February 5, 2018 An international team of researchers (Switzerland, Germany) working on the EU Horizon 2020 project called Phase-Change Switch found that the atomic structure of the metal-insulator vanadium dioxide (VO2) changes as the temperature rises, transitioning from a crystalline structure at room temperature to a metallic one at temperatures above 68°C. They found that adding germanium to VO2 film can lift the material’s phase change temperature to over 100°C required for modern electronic devices. The technology is particularly effective in the frequency range crucial for space communication systems (the Ka band, with programmable frequency modulation between 28.2 and […]
Controlling quantum interactions in a single material
Science Daily February 5, 2018 Using computational simulations, an international team of researchers (USA – Northwestern University, Austria, Germany, China) discovered coexisting quantum-mechanical interactions in the compound silver-bismuth-oxide. Bismuth enables the spin of the electron to interact with its own motion and does not exhibit inversion symmetry. By applying an electric field to the material, researchers were able to control whether the electron spins were coupled in pairs or separated as well as whether the system is electrically conductive or not. The findings could enable ultrafast, low-power electronics and quantum computers that operate faster than current models… read more. Open Access […]
A fast-evolving new botnet could take gadgets in your home to the dark side
MIT Technology Review January 31, 2018 Since December, security researchers have been tracking a malware called Satori, which hijacks internet-connected devices and turns them into “zombies” that can be remotely controlled in unison. After finding a weak point in a device’s defenses, Satori probes to see if the owner has kept default passwords and settings, hoping to exploit these to gain control of the machine. If it succeeds, it then looks for other devices on a network and tries to infect them too. Some of Satori’s source code appear to be the same as that of Mirai, a botnet that […]
Speed of light drops to zero at ‘exceptional points’
Phys org January 31, 2018 An international team of researchers (Israel, Brazil) has theoretically demonstrated a new way to bring light to a standstill at “exceptional points”. Exceptional points can be created in waveguides by varying the gain/loss parameters so that two light modes coalesce. The loss of light can be fixed by using waveguides with parity-time symmetry, as this symmetry ensures that the gain and loss are always balanced. To release the stopped light and accelerate it back up to normal speed, the gain/loss parameters can be reversed. Unlike most other methods that are used to stop light, the […]