A TUNABLE LASER OF SUBMILLIMETER RANGE AND ITS APPLICATION

We performed a comparison of the main parameters of an injectionless s emiconductor laser of the far-IR range on intersubband transitions of hot holes in germanium for two configurations of crossed electric E an d magnetic B fields with respect to the direction of light propagation , namely, for Voigt and Faraday configurations. The areas of the field s E and B where lasing appears, emission spectra, and the temperature range of the laser operation are determined. For the first time, the g ain of radiation by germanium crystal in the fields E perpendicular to B and its dependence upon the polarization of radiation are measured for both configurations of fields by means of a direct method of ampli fication of radiation of another laser. The data obtained give evidenc e of the advantage of the Voigt configuration. A method of narrowing o f the lasing line and of its smooth tuning within the ranges from 70 t o 120 mu m and from 150 to 205 mu m is proposed and tested. For this p urpose we used a smoothly tunable intracavity interferometer. Thus, th e first steps in the construction of a laser spectrometer of the far-I R range are made. The examples of the application of a laser of the fa r-IR range for the study of semiconductors are presented. In particula r, we present the result of the studies of the absorption of light of far-IR range by hot electrons in the course of intraband transitions i n quantum wells on the basis of GaAs/AlGaAs heterostructures.