Suppressed magnetic circular dichroism and valley-selective magneto-absorption due to the effective mass anisotropy in bismuth

Autor: Jean Marie Poumirol, Dirk van der Marel, Julien Levallois, Alexey B. Kuzmenko, M. K. Tran, Pieter J. de Visser, Jérémie Teyssier, Ievgeniia O. Nedoliuk, Ctirad Uher
Rok vydání: 2016
Předmět:
Zdroj: Physical Review Letters, Vol. 117, No 1 (2016) P. 017402
Physical Review Letters
ISSN: 0031-9007
0065-5074
DOI: 10.48550/arxiv.1605.09224
Popis: We have measured the far-infrared reflectivity and Kerr angle spectra on a high-quality crystal of pure semimetallic bismuth as a function of magnetic field, from which we extract the conductivity for left- and right handed circular polarisations. The high spectral resolution allows us to separate the intraband Landau level transitions for electrons and holes. The hole transition exhibits 100% magnetic circular dichroism, it appears only for one polarisation as expected for a circular cyclotron orbit. However the dichroism for electron transitions is reduced to only $13\pm 1$%, which is quantitatively explained by the large effective mass anisotropy of the electron pockets of the Fermi surface. This observation is a signature of the mismatch between the metric experienced by the photons and the electrons. It allows for a contactless measurement of the effective mass anisotropy and provides a direction towards valley polarised magneto-optical pumping with elliptically polarised light.
Databáze: OpenAIRE
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