Wang Yongjian, Legg Henry F, Bömerich Thomas, Park Jinhong, Biesenkamp Sebastian, Taskin A A, Braden Markus, Rosch Achim, Ando Yoichi
Physics Institute II, University of Cologne, Zülpicher Straße 77, 50937 Köln, Germany.
Institute for Theoretical Physics, University of Cologne, Zülpicher Straße 77, 50937 Köln, Germany.
Phys Rev Lett. 2022 Apr 29;128(17):176602. doi: 10.1103/PhysRevLett.128.176602.
Topological materials with broken inversion symmetry can give rise to nonreciprocal responses, such as the current rectification controlled by magnetic fields via magnetochiral anisotropy. Bulk nonreciprocal responses usually stem from relativistic corrections and are always very small. Here we report our discovery that ZrTe_{5} crystals in proximity to a topological quantum phase transition present gigantic magnetochiral anisotropy, which is the largest ever observed to date. We argue that a very low carrier density, inhomogeneities, and a torus-shaped Fermi surface induced by breaking of inversion symmetry in a Dirac material are central to explain this extraordinary property.
具有破缺空间反演对称性的拓扑材料能够产生非互易响应，例如通过磁手性各向异性实现由磁场控制的电流整流。体材料的非互易响应通常源于相对论修正，且总是非常小。在此，我们报告我们的发现：接近拓扑量子相变的ZrTe₅晶体呈现出巨大的磁手性各向异性，这是迄今为止所观测到的最大的磁手性各向异性。我们认为，狄拉克材料中由于空间反演对称性破缺所导致的极低载流子密度、不均匀性以及环形费米面是解释这一非凡特性的关键因素。
