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arXiv · 1510.01840

Fermi surface reconstruction in FeSe under high pressure

Taichi Terashima·Naoki Kikugawa·Andhika Kiswandhi·David Graf·Eun-Sang Choi·James S. Brooks·Shigeru Kasahara·Tatsuya Watashige·Yuji Matsuda·Takasada Shibauchi·Thomas Wolf·Anna E. Böhmer·Frédéric Hardy·Christoph Meingast·Hilbert v. Löhneysen·Shinya Uji
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Abstract

We report Shubnikov-de Haas (SdH) oscillation measurements on FeSe under high pressure up to $P$ = 16.1 kbar. We find a sudden change in SdH oscillations at the onset of the pressure-induced antiferromagnetism at $P$ $\sim$ 8 kbar. We argue that this change can be attributed to a reconstruction of the Fermi surface by the antiferromagnetic order. The negative d$T_c$/d$P$ observed in a range between $P$ $\sim$ 8 and 12 kbar may be explained by the reduction in the density of states due to the reconstruction. The ratio of the transition temperature to the effective Fermi energy remains high under high pressure: $k_BT_c/E_F$ $\sim$ 0.1 even at $P$ = 16.1 kbar.

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Taichi Terashima, Naoki Kikugawa, Andhika Kiswandhi, David Graf, Eun-Sang Choi, James S. Brooks, Shigeru Kasahara, Tatsuya Watashige, Yuji Matsuda, Takasada Shibauchi, Thomas Wolf, Anna E. Böhmer, Frédéric Hardy, Christoph Meingast, Hilbert v. Löhneysen, Shinya Uji. 2016-03-03. Fermi surface reconstruction in FeSe under high pressure. https://doi.org/10.1103/physrevb.93.094505

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