source:scienceAbstractThe study of subtle effects on transport in semiconductors requires high-quality epitaxial structures with low defect density. Using hybrid molecular beam epitaxy (MBE), SrTiO3 films with a low-temperature mobility exceeding 42,000 cm2 V−1 s−1 at a low carrier density of 3 × 1017 cm−3 were achieved. A sudden and sharp decrease in residual resistivity accompanied by an enhancement in the superconducting transition temperature were observed across the second Lifshitz transition where the third band becomes occupied, revealing dominant intraband scattering. These films ...
Release time:
2022
-
05
-
27
viewed：11
source：news.yaleScientists have found a new, nanoscale link between superconductivity — the flow of electric current without a loss of energy — and a phenomenon known as charge density waves.The discovery, which is described in the journal Science, is a tantalizing step in the decades-long search for room-temperature superconductors that could unleash a new generation of electronics and computers.The vast majority of superconducting materials operate at intensely cold temperatures, typically below -320 degrees Fahrenheit, making them impractical to use without a cooling system. Developing supe...
Release time:
2022
-
05
-
26
viewed：12
source：natureAbstractAn optimized sol–gel protocol was carried out to produce an yttrium aluminum garnet (YAG) xerogel from aluminum alkoxide and an yttrium salt on a semi-pilot scale. This xerogel was successfully used without prior pyrolysis as a solid load with the aid of additives in the preparation of pastes. Thermal treatment of the green bodies, obtained by robocasting of the paste, led to cohesive single-phase YAG ceramics. Manufacturing ceramic pieces by additive methods will allow shaping complex forms, while the single step conversion/consolidation would simplify the technological p...
Release time:
2022
-
05
-
25
viewed：17
source:phys.orgResearchers at Northeastern have discovered a new quantum phenomenon in a specific class of materials, called antiferromagnetic insulators, that could yield new ways of powering 'spintronic' and other technological devices of the future.The discovery illuminates 'how heat flows in a magnetic insulator, [and] how [researchers] can detect that heat flow,' says Gregory Fiete, a physics professor at Northeastern and co-author of the research. The novel effects, published in Nature Physics this week and demonstrated experimentally, were observed by combining lanthanum...
Release time:
2022
-
05
-
24
viewed：17