Phys.org August 25, 2020 Classically no information can be transmitted through a completely noisy channel. But with quantum mechanics, adding a second channel actually provides a way to successfully get the information through. Researchers in Australia have shown that by combining the noisy channels such that you don’t know which noisy channel was applied first, it becomes possible to transmit some information. They considered two limiting cases – when both channels are fully depolarising, the ideal limit is communication of 0.049 bits;, when one channel is fully depolarising the ideal limit is communication of 1 bit. Their results offer intriguing […]
A colorful detector: Crystalline material reversibly changes color when absorbing water
Science Daily August 25, 2020 To ensure safety and efficiency factories often need to be monitored for potentially toxic gasses or even excess humidity. Sensors for water vapor are particularly important for monitoring toxic gasses or even excess humidity. But they may have limited lifetimes or require external power. An international team of researchers (Japan, Spain) formed van der Waals porous crystal (VPC-1) from an aromatic dendrimer containing carbon rings anchored to a dibenzophenazine core. Even though van der Waals forces are usually considered to be relatively weak, the crystal stays together during operation. Upon exposure to water vapor, the […]
Cosmic rays may soon stymie quantum computing
MIT News August 26, 2020 Superconducting qubits are used for high-fidelity operations. However, the density of the broken Cooper pairs, referred to as quasiparticles, is orders of magnitude higher than the value predicted at equilibrium suggesting that another generation mechanism exists. A team of researchers in the US (MIT, Pacific Northwest National Laboratory, MIT Lincoln Laboratory) has provided evidence that ionizing radiation from environmental radioactive materials and cosmic rays contributes to this observed difference. The effect of ionizing radiation leads to an elevated quasiparticle density, which they predict would ultimately limit the coherence times of superconducting qubits. They demonstrated that […]
Faster, more efficient energy storage could stem from holistic study of layered materials
Science Daily August 25, 2020 An international team of researchers (USA – Oak Ridge National Laboratory, Georgia State University, Tulane University, Drexel University, Portugal) integrated theoretical data from computational modeling of experimental data to pinpoint potential locations of a variety of charged ions in titanium carbide, the most studied MXene phase. MXenes are a class of two-dimensional materials constructed in layers that are only a few atoms thick. They were able to form links between theory and different types of materials characterization, ranging from very simple to very complex over a wide range of length and time scales. The study’s […]
FEFU scientists are paving way for future tiny electronics and gadgets
EurekAlert August 27, 2020 An international team of researchers (Russia, South Korea, Australia) suggest a new approach to manage spin-electronic properties and functionality of the thin-film magnetic nanosystems. For their experiment they grew a series of palladium films with an ideal single crystal structure. The surface of palladium was coated by thin films of platinum and a magnetic alloy. The system was capped with different variants of materials such as magnesium oxide, tantalum, ruthenium. The capping material influenced the magnetic anisotropy strongly. The deposited Pt and CoFeSiB layers repeated the morphology of the Pd surface. The method is important for […]
New insights into lithium-ion battery failure mechanism
Science Daily August 25, 2020 Ni-rich layered cathode materials are among the most promising candidates for high-energy-density Li-ion batteries, yet their degradation mechanisms are still poorly understood. Researchers in the UK found that as the battery materials expand and shrink the lithium ions move in and out. With prolonged use the atoms at the surface of the material had rearranged to form new structures that are no longer able to store energy. The areas of reconstructed surface apparently act as stakes that pin the rest of the material in place and prevent it from the contraction which is required to […]
New LiDAR Sensor Uses Mirrors to Achieve High Efficiency
IEEE Spectrum August 21, 2020 An international team of researchers (USA – University of Florida, China) designed and fabricated a MEMS mirror specifically designed with direct actuation from the microcontroller. It is powered by a 9-V commercial battery. Instead of a motorized optomechanical scanner, the system relies on MEMS mirrors to control the LiDAR signals. The mirrors require significantly less power to manipulate than the bulkier motorized scanner that have typically been used. A passive infrared sensor ensures that the whole system is only activated when people are present. It may have applications ranging from robotics to small unmanned air […]
A novel approach produces a completely new kind of dynamic light structure
Phys.org August 24, 2020 At a given distance light can dynamically rotate around its center and revolve around another central axis. An international team of researchers (USA – UCSF, Naval Information Warfare Center, University of Rochester, Israel) has shown that combining twisted light and frequency combs together can produce an even more novel structure of light. The beams they simulated achieved mode purity up to 99%, and also had control of the helical phase front. The findings shed insight on our basic understanding of light generation and propagation. This innovation may have future applications in sensing, imaging, manufacturing, and metrology. […]
Photonics researchers report breakthrough in miniaturizing light-based chips
Nanowerk August 27, 2020 Researchers at the University of Rochester made an important step towards miniaturizing functional components on thin-film lithium niobate (LN) platform by developing high-speed LN electro-optic modulators, based upon photonic crystal nanobeam resonators. The devices exhibit a significant tuning efficiency, broad modulation bandwidth of 17.5 GHz, all with a tiny electro-optic modal volume. The modulators enable efficient electro-optic driving of high-Q photonic cavity modes in both adiabatic and non-adiabatic regimes and allow electro-optic switching at 11 Gb s−1 with a bit-switching energy as low as 22 fJ. The demonstration provides a crucial foundation for realizing large-scale LN […]
Researchers create neurons that can be integrated into human brain tissue
Medical Express August 27, 2020 An international team of researchers (Sweden, Ukraine, Spain, Italy) demonstrated that grafted cells integrate into an already established neuronal network, present in a slice of brain cortex from a human donor, receiving inputs and establishing synaptic contacts with the neurons of the slice. The transplantation of cells can be obtained from the same patient, avoiding graft rejection and ethical concerns associated with this kind of therapies…read more. Open Access TECHNICAL ARTICLE