Pressure-induced magnetic collapse and metallization of $\mathrm{TlF}{\mathrm{e}}_{1.6}\mathrm{S}{\mathrm{e}}_{2}$

Pavel G. Naumov; Kai Filsinger; Sergii I. Shylin; Oleg I. Barkalov; Vadim Ksenofontov; Yanpeng Qi; Taras Palasyuk; Walter Schnelle; Sergey A. Medvedev; Martha Greenblatt; Claudia Felser

doi:10.1103/physrevb.96.064109

arXiv · 1708.07702

Pressure-induced magnetic collapse and metallization of $\mathrm{TlF}{\mathrm{e}}_{1.6}\mathrm{S}{\mathrm{e}}_{2}$

Pavel G. Naumov·Kai Filsinger·Sergii I. Shylin·Oleg I. Barkalov·Vadim Ksenofontov·Yanpeng Qi·Taras Palasyuk·Walter Schnelle·Sergey A. Medvedev·Martha Greenblatt·Claudia Felser

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Abstract

The crystal structure, magnetic ordering, and electrical resistivity of TlFe1.6Se2 were studied at high pressures. Below ~7 GPa, TlFe1.6Se2 is an antiferromagnetically ordered semiconductor with a ThCr2Si2-type structure. The insulator-to-metal transformation observed at a pressure of ~ 7 GPa is accompanied by a loss of magnetic ordering and an isostructural phase transition. In the pressure range ~ 7.5 - 11 GPa a remarkable downturn in resistivity, which resembles a superconducting transition, is observed below 15 K. We discuss this feature as the possible onset of superconductivity originating from a phase separation in a small fraction of the sample in the vicinity of the magnetic transition.

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Pavel G. Naumov, Kai Filsinger, Sergii I. Shylin, Oleg I. Barkalov, Vadim Ksenofontov, Yanpeng Qi, Taras Palasyuk, Walter Schnelle, Sergey A. Medvedev, Martha Greenblatt, Claudia Felser. 2017-08-25. Pressure-induced magnetic collapse and metallization of $\mathrm{TlF}{\mathrm{e}}_{1.6}\mathrm{S}{\mathrm{e}}_{2}$. https://doi.org/10.1103/physrevb.96.064109

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