Evolution of vortex pinning in the FeSe$_{1-x}$S$_x$ system

V. A. Vlasenko; A. V. Sadakov; T. A. Romanova; S. U. Gavrilkin; A. V. Dik; O. A. Sobolevskiy; B. I. Massalimov; D. A. Chareev; A. N. Vasiliev; E. I. Maltsev; T. E. Kuzmicheva

doi:10.1088/1361-6668/abd574

arXiv · 2007.09931

Evolution of vortex pinning in the FeSe$_{1-x}$S$_x$ system

V. A. Vlasenko·A. V. Sadakov·T. A. Romanova·S. U. Gavrilkin·A. V. Dik·O. A. Sobolevskiy·B. I. Massalimov·D. A. Chareev·A. N. Vasiliev·E. I. Maltsev·T. E. Kuzmicheva

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Abstract

We present a comprehensive study of vortex matter and pinning evolution in the FeSe$_{1-x}$S$_x$ system with various doping degree. The influence of sulphur substitution on vortex pinning and peak effect occurrence is studied. We show that there is a complex interplay among various pinning contributions in the FeSe$_{1-x}$S$_x$ system. Additionally, we study a possible vortex liquid-vortex glass/lattice transition and find an evidence that the vortex liquid-vortex glass phase transition in FeSe has a quasi two-dimensional nature. We investigate the upper critical field behaviour in FeSe$_{1-x}$S$_x$ system, and found that the upper critical field is higher than that predicted by the Werthamer-Helfand-Hohenberg (WHH) model, whereas its temperature dependence could be fitted within a two-band framework. Finally, a detailed H-T phase diagram is presented.

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V. A. Vlasenko, A. V. Sadakov, T. A. Romanova, S. U. Gavrilkin, A. V. Dik, O. A. Sobolevskiy, B. I. Massalimov, D. A. Chareev, A. N. Vasiliev, E. I. Maltsev, T. E. Kuzmicheva. 2020-07-20. Evolution of vortex pinning in the FeSe$_{1-x}$S$_x$ system. https://doi.org/10.1088/1361-6668/abd574

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