Superconductivity in hole-doped germanium point contacts

Fuente: arXiv
Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: Gamayunova, N. V., Kuzmiak, M., Szabo, P., Samuely, P., Naidyuk, Yu. G.
Format: Preprint
Veröffentlicht: 2021
Schlagworte:
Online-Zugang:
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
_version_ 1866914528882589696
author Gamayunova, N. V.
Kuzmiak, M.
Szabo, P.
Samuely, P.
Naidyuk, Yu. G.
author_facet Gamayunova, N. V.
Kuzmiak, M.
Szabo, P.
Samuely, P.
Naidyuk, Yu. G.
contents We have observed superconductivity in heavy p-doped Ge by measuring of differential resistance dV/dI(V) of Ge - PtIr point contacts. The superconducting (SC) features disappear above 6 K or above 1 T, what can be taken as the critical temperature and the critical magnetic field, respectively. The observed dV/dI(V) spectrum with Andreev reflection like features was fitted within one-gap Blonder-Tinkham-Klapwijk model. The extracted SC gap demonstrates Bardeen-Cooper-Schrieffer-like behavior with 2 Delta/kBTc = 10+/-1 ratio, which is much higher that expected for conventional superconductors. Magnetic field suppresses Andreev reflection features, but the SC gap moderately decreases in magnetic field similarly as it was observed previously for the type-II superconductors, including nickel borocarbide and iron-based superconductors. Curiously, we have not yet observed superconductivity in n-doped Ge with a similar dopant concentration.
format Preprint
id arxiv_https___arxiv_org_abs_2109_01364
institution arXiv
publishDate 2021
record_format arxiv
spellingShingle Superconductivity in hole-doped germanium point contacts
Gamayunova, N. V.
Kuzmiak, M.
Szabo, P.
Samuely, P.
Naidyuk, Yu. G.
Superconductivity
We have observed superconductivity in heavy p-doped Ge by measuring of differential resistance dV/dI(V) of Ge - PtIr point contacts. The superconducting (SC) features disappear above 6 K or above 1 T, what can be taken as the critical temperature and the critical magnetic field, respectively. The observed dV/dI(V) spectrum with Andreev reflection like features was fitted within one-gap Blonder-Tinkham-Klapwijk model. The extracted SC gap demonstrates Bardeen-Cooper-Schrieffer-like behavior with 2 Delta/kBTc = 10+/-1 ratio, which is much higher that expected for conventional superconductors. Magnetic field suppresses Andreev reflection features, but the SC gap moderately decreases in magnetic field similarly as it was observed previously for the type-II superconductors, including nickel borocarbide and iron-based superconductors. Curiously, we have not yet observed superconductivity in n-doped Ge with a similar dopant concentration.
title Superconductivity in hole-doped germanium point contacts
topic Superconductivity
url https://arxiv.org/abs/2109.01364