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arXiv · 1705.06395

Robust short-range-ordered nematicity in FeSe evidenced by high-pressure NMR

P. S. Wang·P. Zhou·S. S. Sun·Y. Cui·T. R. Li·Hechang Lei·Ziqiang Wang·Weiqiang Yu
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Abstract

We report high-pressure $^{77}$Se NMR studies on FeSe single crystals that reveal a prominent inhomogeneous NMR linewidth broadening upon cooling, with the magnetic field applied along the tetragonal [110] direction. The data indicate the existence of short-range-ordered, inhomogeneous electronic nematicity, which has surprisingly long time scales over milliseconds. The short-range order survives temperatures up to $8$ times the structural transition temperature, and remains robust against pressure, in contrast to the strong pressure-dependence of the orbital ordering, structural transition, and the ground state magnetism. Such an extended region of static nematicity in the ($P$,$T$) space of FeSe indicates an enormously large fluctuating regime, and provide fresh insights and constraints to the understanding of electronic nematicity in iron-based superconductors.

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P. S. Wang, P. Zhou, S. S. Sun, Y. Cui, T. R. Li, Hechang Lei, Ziqiang Wang, Weiqiang Yu. 2017-09-18. Robust short-range-ordered nematicity in FeSe evidenced by high-pressure NMR. https://doi.org/10.1103/physrevb.96.094528

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