Two-photon and three-photon spectroscopy of ZnO under uniaxial stress

Abstract
Using two-photon excitation spectroscopy and three-photon difference frequency generation, resonances on the transverse and longitudinal polariton branches of the A(Γ5), B(Γ5), and C(Γ1) 1S excitons of ZnO are studied under uniaxial stress. Due to the small linewidth, shifts and splittings are clearly resolved and six deformation potentials are determined with high accuracy.