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arXiv · 2006.01657

Revealing Hidden Orbital Pseudospin Texture with Time-Reversal Dichroism in Photoelectron Angular Distributions

Samuel Beaulieu·Jakub Schusser·Shuo Dong·Michael Schüler·Tommaso Pincelli·Maciej Dendzik·Julian Maklar·Alexander Neef·Hubert Ebert·Karol Hricovini·Martin Wolf·Jürgen Braun·Laurenz Rettig·Jan Minár·Ralph Ernstorfer
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Abstract

We performed angle-resolved photoemission spectroscopy (ARPES) of bulk 2H-WSe$_2$ for different crystal orientations linked to each other by time-reversal symmetry. We introduce a new observable called time-reversal dichroism in photoelectron angular distributions (TRDAD), which quantifies the modulation of the photoemission intensity upon effective time-reversal operation. We demonstrate that the hidden orbital pseudospin texture leaves its imprint onto TRDAD, due to multiple orbitals interference effects in photoemission. Our experimental results are in quantitative agreement with both tight-binding model and state-of-the-art fully relativistic calculations performed using the one-step model of photoemission. While spin-resolved ARPES probes the spin component of entangled spin-orbital texture in multiorbital systems, we unambiguously demonstrate that TRDAD reveals its orbital pseudospin texture counterpart.

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Samuel Beaulieu, Jakub Schusser, Shuo Dong, Michael Schüler, Tommaso Pincelli, Maciej Dendzik, Julian Maklar, Alexander Neef, Hubert Ebert, Karol Hricovini, Martin Wolf, Jürgen Braun, Laurenz Rettig, Jan Minár, Ralph Ernstorfer. 2020-06-02. Revealing Hidden Orbital Pseudospin Texture with Time-Reversal Dichroism in Photoelectron Angular Distributions. https://doi.org/10.1103/physrevlett.125.216404

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