Hydrogen-impurity-induced conductance peaks in constriction type Josephson junctions

We studied hydrogen (H) and deuterium (D) impurity effects of superconducting Josephson current flowing through the superconductor-constriction-superconductor Josephson junctions (ScS-JJ). When H or D impurities are adsorbed on the surface of the ScS-JJ prepared by niobium (Nb) or lead (Pb), many spike-like peaks with almost the same spacing appear inside the superconducting gap in addition to anomalies owing to the multiple Andreev reflection in the differential conductance spectra. The spacing between the adjacent peaks is independent of the temperature variation. These indicate that H or D impurities adsorbed on the JJ are sources of noise for the Josephson current.

Modelling isolated hydrogen impurity in Lu2O3 with muonium spectroscopy

We identified in this experiment two muon configurations in Lu2O3, the oxygen-bound (O-Mu+) ground state and a metastable (energy barrier 0.7(3) eV) atom-like excited state. These configurations are partially not formed immediately after implantation but somewhat delayed due to the requirement of a lattice rearrangement around the muon. These rearrangement processes occur on a timescale of ns to µs and are thus observable in µSR experiments. A special role plays a fairly long-lived (ns to µs) transition state as an intermediate step in the reaction process.

Исследование влияния атомарного состава на скорость плазмохимического травления нитрида кремния в силовых транзисторах на основе AlGaN/GaN-гетероперехода

The effect of atomic composition on the rate of plasma chemical etching of silicon nitride in power transistors based on an AlGaN / GaN heterojunction is studied. It is shown how the subsequent process of its plasma-chemical etching depends on the configuration of the incorporation of hydrogen impurity atoms into the molecular structure of the silicon nitride deposited in the plasma. The dependence of the etching rate on the parameters of the process (the working pressure in the chamber, the power of the plasma generator, the flow of working gases, the deposition temperature) is investigated. It was shown that the etching rate of the HxSirNzHy film does not depend directly on the hydrogen content, but significantly depends on the ratio of [Si-H] / [N-H] bonds. The etching rate of HxSirNzHy in a high-density plasma at low powers is much less dependent on the configuration of hydrogen bonds than the etching rate of this dielectric in a buffer etchant.