PT  - JOURNAL ARTICLE
AU  - Schüler, Michael
AU  - De Giovannini, Umberto
AU  - Hübener, Hannes
AU  - Rubio, Angel
AU  - Sentef, Michael A.
AU  - Werner, Philipp
TI  - Local Berry curvature signatures in dichroic angle-resolved photoelectron spectroscopy from two-dimensional materials
AID  - 10.1126/sciadv.aay2730
DP  - 2020 Feb 01
TA  - Science Advances
PG  - eaay2730
VI  - 6
IP  - 9
4099  - http://advances.sciencemag.org/content/6/9/eaay2730.short
4100  - http://advances.sciencemag.org/content/6/9/eaay2730.full
SO  - Sci Adv2020 Feb 01; 6
AB  - Topologically nontrivial two-dimensional materials hold great promise for next-generation optoelectronic applications. However, measuring the Hall or spin-Hall response is often a challenge and practically limited to the ground state. An experimental technique for tracing the topological character in a differential fashion would provide useful insights. In this work, we show that circular dichroism angle-resolved photoelectron spectroscopy provides a powerful tool that can resolve the topological and quantum-geometrical character in momentum space. In particular, we investigate how to map out the signatures of the momentum-resolved Berry curvature in two-dimensional materials by exploiting its intimate connection to the orbital polarization. A spin-resolved detection of the photoelectrons allows one to extend the approach to spin-Chern insulators. The present proposal can be extended to address topological properties in materials out of equilibrium in a time-resolved fashion.