Influence of After-Growth Treatments on the Optical Parameters of Teraherz ZnGeP2 Crystals

Russian Physics Journal - Results of investigations are presented of the THz spectra of the refractive index n(v) and of the extinction coefficient k(v) for ZnGeP2 single crystals with different...     

Growth of ZnGeP<Subscript>2</Subscript> crystals from melt

Some features of the growth of ZnGeP₂ single crystals by the Bridgman method have been considered. The ratio of the thermal-conductivity coefficients of the liquid and solid phases of ZnGeP₂ at the melting temperature was estimated to be 2.3. It is established that, in the case of ZnGeP₂ growth on a seed, the most favorable crystallographic directions are 〈100〉 and 〈001〉. It is shown that annealing and electron irradiation significantly decrease the optical absorption coefficient in the impurity absorption region.     

Simulation of parametric oscillation in the submillimeter range at pumping of the ZnGeP2 crystal by a train of 100-ps high-power pulses

Analysis is given for a possibility of singly resonant parametric oscillation in the submillimeter range at synchronous pumping of the ZnGeP₂ crystal by a train of 100-ps second-harmonic pulses from the CO₂ laser with the radiation energy 1.0 J. The calculation shows that using the ZnGeP₂ crystal and the second harmonic of the CO₂ laser with the energy density 1.8 J cm⁻², one can get the peak submillimeter radiation power from 3.6 to 12 MW in the range from 95 to 300 μm (1.0–3.3 THz). The expected peak power values are larger than the experimental ones obtained by other nonlinear optics methods.     

Behavior of impurity copper in ZnGeP2 single crystals with diffusion doping

Results from a study of electrophysical and luminescent properties of zinc-germanium diphosphide single crystals, diffusion doped with copper, are presented. The nature of the dominant defects formed upon copper diffusion in ZnGeP₂ is determined using a thermodynamic analysis of defect formation processes in ZnGeP₂ and a ZnGeP₂: Cu solid solution performed within the framework of the quasichemical analysis method. It is demonstrated that by choosing the copper diffusion method the hole concentration in the ZnGeP₂ can be varied over the range 10¹²–10¹⁶ cm^–3. A retrograde character was observed in copper solubility in ZnGeP₂ compounds. Defect formation processes in ZnGeP₂ upon copper diffusion depend on the degree of atomic ordering in the cation sublattice at the diffusion annealing temperature.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 2, pp. 64–69, February, 1985.     

Effect of electron irradiation of ZnGeP2 single crystals on terahertz losses in a wide temperature range

Physics of the Solid State - The reflection and transmission spectra of ZnGeP2 single crystals irradiated with 4-MeV electrons have been measured in the frequency range of 5-5000 cm−1 at...     

Far infrared generation by CO2 lasers frequencies subtraction in a ZnGeP2 crystal

a pulsed radiation power of the order of 1W in the submillimeter range (102–110 µm) was reached for the first time, with the aid of a ZnGeP₂ crystal, at the difference frequency of CO₂ laser radiations.     

Effect of Post-Growth Treatments on the ZnGeP2 Single Crystal Optical Properties in THz Range

Russian Physics Journal -     

Diagnostics of Inclusions in ZnGeP2 Crystals by the Method of Terahertz Spectroscopy

Russian Physics Journal - Results of experimental investigations of the dispersion of the refractive index n(ν) and of the absorption coefficient α(ν) of a ZnGeP2 crystal in the...