Heat capacity and Mosssbauer study of Self flux grown FeTe Single Crystal

TL;DR

This study investigates the heat capacity and Mössbauer spectra of self-flux grown FeTe single crystals, revealing a coupled structural/magnetic transition at 70K and detailed magnetic properties.

Contribution

It provides detailed heat capacity and Mössbauer analysis of FeTe single crystals, elucidating their phase transition and magnetic characteristics for the first time.

Findings

Structural/magnetic transition at 70K confirmed by heat capacity.

Mössbauer spectra show paramagnetic and magnetic states at different temperatures.

Debye temperature of 324K estimated from heat capacity fitting.

Abstract

We report mainly the heat capacity and Mossbauer study of self flux grown FeTe single crystal, which is ground state compound of the Fe chalcogenides superconducting series, i.e., FeTe1-x(Se/S)x. The as grown FeTe single crystal is large enough to the tune of few cm and the same crystallizes in tetragonal structure having space group of P4/nmm. FeTe shows the structural/magnetic phase transition at 70K in both magnetic and resistivity measurements. Heat capacity measurement also confirms the coupled structural/magnetic transition at the same temperature. The Debye model fitting of low temperature (below 70K) heat capacity exhibited Debye temperature to be 324K. M\"Ossbauer spectra are performed at 300K and 5K. The 300K spectra showed two paramagnetic doublets and the 5K spectra exhibited hyperfine magnetic sextet with an average hyperfine field of 10.6Tesla matching with the results of Yoshikazu Mizuguchi et al.