Magneto-Stark-effect of yellow excitons in cuprous oxide

TL;DR

This study explores the Magneto-Stark effect on yellow excitons in cuprous oxide, comparing experimental and numerical spectra in different magnetic field configurations to understand symmetry effects and spectral line changes.

Contribution

It extends previous research by analyzing the Magneto-Stark effect in the Voigt configuration, revealing how it influences excitonic spectra and symmetry in cuprous oxide.

Findings

Magneto-Stark effect increases the number of allowed spectral lines.

The Voigt configuration introduces an effective electric field affecting exciton spectra.

Experimental and numerical results are consistent in showing symmetry reduction.

Abstract

We investigate and compare experimental and numerical excitonic spectra of the yellow series in cuprous oxide Cu$_2$O in the Voigt configuration and thus partially extend the results from Schweiner et al. [Phys. Rev. B 95, 035202 (2017)], who only considered the Faraday configuration. The main difference between the configurations is given by an additional effective electric field in the Voigt configuration, caused by the motion of the exciton through the magnetic field. This Magneto-Stark effect was already postulated by Gross et al. and Thomas et al. in 1961 [Sov. Phys. Solid State 3, 221 (1961); Phys. Rev. 124, 657 (1961)]. Group theoretical considerations show that the field most of all significantly increases the number of allowed lines by decreasing the symmetry of the system. This conclusion is supported by both the experimental and numerical data.