Coherent spin dynamics of excitons in strained monolayer semiconductors

M. M. Glazov

Published 2022-10-13Version 1

We develop a model of the exciton spin-valley dynamics in two-dimensional transition metal dichalcogenides under elastic strain. The strain splits the exciton radiative doublet in linearly polarizes states. Consequently, it induces an effective magnetic field acting on the exciton pseudospin and causes its precession. As a result, circular polarization of excitons oscillates with time and time-oscillating linear polarization appears. We study competition of the strain-induced effective magnetic field with the field caused by the exciton longitudinal-transverse splitting. We uncover different regimes of coherent spin dynamics of two-dimensional excitons and show, in particular, that for sufficiently large strain-induced and longitudinal-transverse splittings two frequencies related to these splittings appear in the exciton circular polarization beats.