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arXiv · 1405.7749

Anomalous Fermi surface in FeSe seen by Shubnikov-de Haas oscillation measurements

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

We have observed Shubnikov-de Haas oscillations in FeSe. The Fermi surface deviates significantly from predictions of band-structure calculations and most likely consists of one electron and one hole thin cylinder. The carrier density is in the order of 0.01 carriers/ Fe, an order-of-magnitude smaller than predicted. Effective Fermi energies as small as 3.6 meV are estimated. These findings call for elaborate theoretical investigations incorporating both electronic correlations and orbital ordering.

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Taichi Terashima, Naoki Kikugawa, Andhika Kiswandhi, Eun-Sang Choi, James S. Brooks, Shigeru Kasahara, Tatsuya Watashige, Hiroaki Ikeda, Takasada Shibauchi, Yuji Matsuda, Thomas Wolf, Anna E. Böhmer, Frédéric Hardy, Christoph Meingast, Hilbert v. Löhneysen, Michi-To Suzuki, Ryotaro Arita, Shinya Uji. 2014-05-30. Anomalous Fermi surface in FeSe seen by Shubnikov-de Haas oscillation measurements. https://doi.org/10.1103/physrevb.90.144517

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