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arXiv · 1807.00339

Spin-resolved electronic response to the phase transition in MoTe$_2$

Andrew P. Weber·Philipp Rüßmann·Nan Xu·Stefan Muff·Mauro Fanciulli·Arnaud Magrez·Philippe Bugnon·Helmuth Berger·Nicholas C. Plumb·Ming Shi·Stefan Blügel·Phivos Mavropoulos·J. Hugo Dil
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Abstract

The semimetal MoTe$_2$ is studied by spin- and angle- resolved photoemission spectroscopy to probe the detailed electronic structure underlying its broad range of response behavior. A novel spin-texture is uncovered in the bulk Fermi surface of the non-centrosymmetric structural phase that is consistent with first-principles calculations. The spin-texture is three-dimensional, both in terms of momentum dependence and spin-orientation, and is not completely suppressed above the centrosymmetry-breaking transition temperature. Two types of surface Fermi arc are found to persist well above the transition temperature. The appearance of a large Fermi arc depends strongly on thermal history, and the electron quasiparticle lifetimes are greatly enhanced in the initial cooling. The results indicate that polar instability with strong electron-lattice interactions exists near the surface when the bulk is largely in a centrosymmetric phase.

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Andrew P. Weber, Philipp Rüßmann, Nan Xu, Stefan Muff, Mauro Fanciulli, Arnaud Magrez, Philippe Bugnon, Helmuth Berger, Nicholas C. Plumb, Ming Shi, Stefan Blügel, Phivos Mavropoulos, J. Hugo Dil. 2018-07-01. Spin-resolved electronic response to the phase transition in MoTe$_2$. https://doi.org/10.1103/physrevlett.121.156401

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