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arXiv · 2103.09701

Control of band structure of FeSe single crystals via biaxial strain

M. Nakajima·Y. Ohata·S. Tajima
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Abstract

We performed systematic transport measurements on FeSe single crystals with applying in-plane biaxial strain $\varepsilon$ ranging from -0.96% to 0.23%. Biaxial strain was introduced by firmly gluing samples to various substrate materials with different thermal expansion. With increasing $\varepsilon$, structural and superconducting transition temperatures monotonically increased and decreased, respectively. We analyzed magneto-transport results using a compensated three-carrier model. The evaluated densities of hole and electron carriers systematically changed with strain. This indicates that we succeeded in controlling the band structure of single-crystalline FeSe.

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M. Nakajima, Y. Ohata, S. Tajima. 2021-03-17. Control of band structure of FeSe single crystals via biaxial strain. https://doi.org/10.1103/physrevmaterials.5.044801

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