Electron-phonon interaction in transition metal diborides TB_2 (T=Zr, Nb, Ta) studied by point-contact spectroscopy

TL;DR

This study investigates the electron-phonon interaction in transition metal diborides ZrB_2, NbB_2, and TaB_2 using point-contact spectroscopy, revealing low EPI parameters and comparing features relevant to superconductivity in MgB_2.

Contribution

It provides the first detailed point-contact spectroscopy analysis of EPI in ZrB_2, NbB_2, and TaB_2, highlighting their low EPI strength and similarities to MgB_2.

Findings

EPI parameters lambda<0.1 for all compounds

Identified common features in EPI functions

Discussed implications for superconductivity

Abstract

The electron-phonon interaction (EPI) in transition metal diborides TB_2 (T=Zr, Nb, Ta) is investigated by point-contact (PC) spectroscopy. The PC EPI functions were recovered and the EPI parameters lambda<0.1 were estimated for all three compounds. Common and distinctive features between the EPI functions for those diborides are discussed also in connection with the superconductivity in MgB_2.