The Temperature Dependence of an Absorption Feature in the Vicinity of the Long Wavelength Transmission Cutoff in ZnSe

The temperature dependence of the infrared absorption spectrum of ZnSe was measured by using a variable temperature, liquid nitrogen cooled, absorption cell interfaced with a Fourier transform infrared spectrometer. Absorption difference spectra were obtained as a function of temperature by using the on-board computing facilities of the spectrometer coupled with its data storage capabilities. The temperature dependence of the absorption feature, which extends from about 450 to 800 cm ⁻¹, is shown to be consistent with a two phonon interaction as have been previously suggested.