Metal that withstands ultra-high temperature and pressure identified

Science Daily  September 27, 2018 Researchers in Japan analyzed the ultrahigh-temperature tensile creep behaviour of a TiC-reinforced Mo-Si-B-based alloy in the range of 1400–1600 °C at constant true stress range in vacuum. It displayed excellent creep strength with relatively reasonable creep parameters and moderate strain-rate oscillations. The findings have applications in aircraft jet engines and gas turbines for electric power generation…read more. Open Access TECHNICAL ARTICLE

UTokyo researchers generate the strongest-ever controllable magnetic field

University of Tokyo  September 18, 2018 To generate the magnetic field researchers in Japan built a sophisticated device capable of electromagnetic flux-compression (EMFC), a method of magnetic field generation well-suited for indoor operations. Using the device, they were able to produce a magnetic field of 1,200 teslas, sustain it for 100 microseconds, thousands of times longer than previous attempts, and control the magnetic field so it didn’t destroy their equipment like some past attempts to create powerful fields. The research could lead to powerful investigative tools for material scientists and may have applications in fusion power generation… read more. Open […]

Dual-layer solar cell sets record for efficiently generating power

Nanowerk  August 31, 2018 The combination of hybrid perovskite and Cu(In,Ga)Se2 (CIGS) has the potential for realizing high-efficiency thin-film tandem solar cells because of the complementary tunable bandgaps and excellent photovoltaic properties of these materials. Researchers in Japan used nanoscale interface engineering of the CIGS surface and a heavily doped poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA) hole transport layer between the subcells that preserves open-circuit voltage and enhances both the fill factor and short-circuit current. The solar cell achieved a 22.43% efficiency, and unencapsulated devices under ambient conditions maintained 88% of their initial efficiency after 500 hours of aging under continuous 1-sun illumination… read […]

Another step forward on universal quantum computer

Phys.org  August 13, 2018 Researchers in Japan have demonstrated non-adiabatic and non-abelian holonomic quantum gates over a geometric spin qubit on an electron or nitrogen nucleus, which paves the way to realizing a universal quantum computer. To avoid unwanted interference, they used a degenerate subspace of the triplet spin qutrit to form an ideal logical qubit in an NV center. This method facilitated fast and precise geometric gates at a temperature below 10 K, and the gate fidelity was limited by radiative relaxation. Based on this method, in combination with polarized microwaves, they succeeded in the manipulation of the geometric […]

Superflexible aerogels are highly efficient absorbents, thermal insulators, and pressure sensors

Phys.org  July 26, 2018 Researchers in Japan have introduced extremely elastic aerogels that are easy to process and can be produced at low cost. Their success relies on a doubly cross-linked organic-inorganic network structure with adjustable network density. The delicate structures are highly elastic. They can be bent, rolled, twisted, and cut into desired shapes. The more densely crosslinked versions exhibit high thermal insulation, surpassing conventional materials like polyurethane foam. When exposed to a mixture of hexane and water, they exclusively absorb the hexane, which can subsequently be removed by squeezing the material like a sponge or by evaporation. This […]

Using spin current to convert mechanical vibrations into electricity

Nanowerk  July 20, 2018 Researchers in Japan have designed a nanoscale device that converts mechanical ripples into an electrical current via a spin current. They found that the spin current generated in the second layer was large enough to move magnetic domain walls, which could be used in memory devices. It is still below the spin currents needed, but they could be increased by optimizing the devices. The technology could be used in devices that permit sound waves to pass in one direction but block them in the opposite direction… read more. TECHNICAL ARTICLE

High-power thermoelectric generator utilizes thermal difference of only 5C

Phys.org  July 6, 2018 Long silicon nanowires needed in the silicon-based thermoelectric generators to secure temperature difference across the silicon wire weakens the strength of the devices. To overcome this, researchers developed thermoelectric generator eliminating the cavity structure but instead shortened the silicon nanowires to 0.25 nanometers. Thermal resistance was suppressed, and the power density multiplied ten times by thinning the generator’s silicon substrate from the conventional 750 nanometers to 50 nanometers with backside grinding. The device has applications in IoT… read more.

A fresh sensation in sensing technology

Phys.org  June 01, 2018 In optical fiber sensor networks a fiber Bragg grating is one of the key sensor devices used because of compactness and immunity to electromagnetic interference. But their sensitivity is not always satisfactory. Researchers in Japan have developed an inexpensive super spectral resolution method for multi-channel spectrometers to conventional interrogators for optical fiber sensing. The technology may find applications in IoT… read more. TECHNICAL ARTICLE

The right squeeze for quantum computing

Phys.org  June 01, 2018 Inherent properties of photons in light are used for encoding information as quantum bits into a light beam by digitizing patterns of the electromagnetic field. “Squeezing” light is used to reduce errors from light waves during quantum computation. Researchers in Japan have developed a theoretical model that uses both the properties of quantum bits and the modes of the electromagnetic field in which they exist. The approach involves squeezing light by removing error-prone quantum bits when quantum bits cluster together. According to the researchers this model is 10 billion times more tolerant to errors than current […]

Keep the light off: A material with improved mechanical performance in the dark

Phys.org  May 17, 2018 Researchers in Japan have shown that when crystals of zinc sulfide are kept in the dark at room temperature, they deformed plastically without fracture until a large strain of 45%. The high plasticity was accompanied by a considerable decrease in the band gap of the deformed crystals increasing their electrical conductivity which may be controlled by mechanical deformation. According to the researchers the decreased band gap was caused by deformation introducing dislocations into the crystals, which changed their band structure. The findings open avenue to optimize the performance of inorganic semiconductors in electronics… read more. TECHNICAL […]