Resonant two-photon absorption in a tetragonal CdP2

Kinetic, spectral, intensity, angular, and polarization of resonant two-photon absorption (TPA) in β-CdP2 has been investigated. Resonant TPA was observed for which the total energy of the two photons was 2.60 eV. It is shown that resonant TPA takes place via a real intermediate level d3 in the band gap at the depth Ec-0.86 eV. The electron transverse relaxation time for resonant TPA, the cross section for absorption of laser photons in d3→C transitions, the equilibrium population of d3 centers in a doped n-type sample, and the resonant TPA constant were determined as 4.3×10−14 s, 1.25×10−17 cm2, 0.95, and 0.028 cm/MW, respectively.