Two-photon spectroscopy of ZnSe under uniaxial stress

Optical harmonic generation on the exciton-polariton in ZnSe

“…The fit allows to obtain the values of the exciton parameters: E T = 2.80268 eV, E L = 2.80389 eV, ω LT = 1.21 meV, and Γ = 1.2 meV. These values are in accordance with literature data [21,22,27]. We used ε = 5.5 as the background dielectric constant and M ≈ 0.8m 0 as exciton translational mass.…”

“…We compare the reflectivity and the SHG spectrum with the exciton-polariton dispersion of the 1S exciton in ZnSe, taken from Ref. [27], see Fig. 3, to assign the observed features to particular states.…”

“…In Figure 7, the dispersion of the 1S exciton-polariton in ZnSe with the UPB and LPB is plotted [27]. The longitudinal, E L , and transversal, E T , exciton energies are given by the dashed and dotted lines, respectively.…”

“…The semiconductor ZnSe has a large exciton binding energy of 20 meV leading to pronounced excitonpolariton properties [21,22], which makes it an attractive model system for nonlinear optical spectroscopy. Its exciton-polariton dispersion is well studied by various experimental techniques: resonant Brillouin scattering [22][23][24], two-photon resonant Raman scattering [25], and two-photon excitation of photoluminescence [26,27]. We showed recently that the exciton-polariton in ZnSe can be also addressed by SHG [4] and THG [11].…”

Exchange and radiative lifetimes for close Frenkel pairs on the zinc sublattice of ZnSe

“…On the other hand, two more recent experiments conclude that JϭϪ1.2 meV ͑Ref. 14͒ or JϭϪ1.32 meV, 15 corresponding to J 0 Ϸ5 eV. In either extreme, however, our value here of 0.9 eV is clearly in the right range, and we conclude therefore that the simple treatment that we have outlined above is leading to reasonable values for the Frenkel pair exchange.…”