Regensburg 2022 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
MM: Fachverband Metall- und Materialphysik
MM 18: Poster Session 2
MM 18.38: Poster
Tuesday, September 6, 2022, 17:30–20:00, P2
Electron-phonon interaction and point contact enhanced superconductivity in trigonal PtBi2 — Dmytro Bashlakov1, •Oksana Kvitnitskaya1, Grigory Shipunov2, Saicharan Aswartham2, Oleg Feya2,3, Dmitri Efremov2, Bernd Büchner2,4, and Yu. G. Naidyuk1 — 1B. Verkin Institute for Low Temperature Physics and Engineering, NAS of Ukraine, Kharkiv, Ukraine — 2Institute for Solid State Research, IFW Dresden, Dresden, Germany — 3Kyiv Academic University, Kyiv, Ukraine — 4Institut für Festkörper- und Materialphysik and Würzburg-Dresden Cluster of Excellence ct.qmat, Technische Universität Dresden, Dresden, Germany
PtBi2 is a Weyl semimetal, which demonstrates superconductivity with low critical temperature Tc ~ 0.6 K in the bulk. Here, we report our study of electron-phonon interaction (EPI) in trigonal PtBi2 by the Yanson point contact (PC) spectroscopy and presenting the observation of PC enhanced superconductivity. We show, that the Yansons PC spectra display a broad maximum around 15 meV, indicating, apparently, EPI mechanism of Cooper pairing in PtBi2. Moreover, we discovered a substantial increase of Tc up to ~ 3.5 K in PCs. The observed Tc is sufficiently higher than the bulk value, as well as detected at hydrostatic pressure. We calculated the phonon density of states and Eliashberg EPI function in PtBi2 within the framework of the density functional theory. A comparison of experimental data with theoretical calculations showed acceptable agreement. The theoretical Tc is 3.5 K, which corresponds to the experimental value.