Interplay of superconductivity and magnetism in FeSe$_{1-x}$Te$_x$ compounds. Pressure effects

A. S. Panfilov; V. A. Pashchenko; G. E. Grechnev; V. A. Desnenko; A. V. Fedorchenko; A. G. Grechnev; A. N. Bludov; S. L. Gnatchenko; D. A. Chareev; E. S. Mitrofanova; A. N. Vasiliev

doi:10.1063/1.4890990

arXiv · 1311.4656

Interplay of superconductivity and magnetism in FeSe$_{1-x}$Te$_x$ compounds. Pressure effects

A. S. Panfilov·V. A. Pashchenko·G. E. Grechnev·V. A. Desnenko·A. V. Fedorchenko·A. G. Grechnev·A. N. Bludov·S. L. Gnatchenko·D. A. Chareev·E. S. Mitrofanova·A. N. Vasiliev

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Abstract

The influence of uniform pressures $P$ up to 5 kbar on the superconducting transition temperature $T_c$ was studied for the FeSe$_{1-x}$Te$_x$ ($x=0$, 0.85, 0.88 and 0.9) system. For the first time, we observed a change in sign of the pressure effect on $T_c$ when going from FeSe to tellurium rich alloys. This has allowed to specify the pressure derivative d$T_c$/d$P$ for the system as a function of composition. The observed dependence was compared with results of the {\em ab initio} calculations of electronic structure and magnetism of FeSe, FeTe and FeSe$_{0.5}$Te$_{0.5}$, and also with our recent experimental data on pressure effects on magnetic susceptibilities of FeSe and FeTe compounds in the normal state. This comparison demonstrates a competing interplay between superconductivity and magnetism in tellurium rich FeSe$_{1-x}$Te$_x$ compounds

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A. S. Panfilov, V. A. Pashchenko, G. E. Grechnev, V. A. Desnenko, A. V. Fedorchenko, A. G. Grechnev, A. N. Bludov, S. L. Gnatchenko, D. A. Chareev, E. S. Mitrofanova, A. N. Vasiliev. 2013-11-19. Interplay of superconductivity and magnetism in FeSe$_{1-x}$Te$_x$ compounds. Pressure effects. https://doi.org/10.1063/1.4890990

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