Study of exciton-photon coupling in CuCl semiconductor microcavities with large decay of cavity photons
Phys. Rev. B 113, 115309 – Published 20 March, 2026
DOI: https://doi.org/10.1103/6ng9-4vqy
Abstract
In CuCl semiconductor microcavities with large decay of the cavity photon (CP), we have studied the dependence of the coupling energy between excitons and CPs on the position of the active layer in the cavity layer, using angle-resolved transmission (ART) spectroscopy. The ART spectra show that the characteristic energies and spectral widths of three cavity polariton branches depend on the incident angle of the probe light, and the spectral profiles of the respective branches also change between the symmetric and asymmetric structures. The incident-angle dependence of the characteristic energies and spectral widths of the respective branches extracted by the asymmetric spectral function is interpreted by the complex eigenvalues of the non-Hermitian effective Hamiltonian. This analysis in terms of an open quantum system allows us to estimate the coupling energy even in the weak coupling regime by considering the decay rates of CPs and excitons. From the analytical results, it is found that the coupling energies of the cavity polaritons depend on the position of the active layer, which indicates that the exciton-photon coupling changes between the strong and weak coupling regimes. Moreover, we discuss the active-layer position dependence of the coupling energy by considering the overlap integral of the exciton polarization and electric field of the CP.
