Bismuth, antimony and its alloys are the typical representatives of a class of half-metals, electric conducting of which in 10{sup}2-10{sup}3 times is lower, than at usual metals, well conducting an electrical current. The alloys bismuth with antimony have semi-conductor properties in wide area of structures at temperatures below 77 0{sup left}K.However, they are isolators at temperatures close to 0 0{sup left}K. The electrical properties bismuth, antimony and its alloys considerably differ from properties of usual metals. That is determined by complexity of its zoned structure and presence rather poorly of degenerated carriers of a charge-electrons and holes. It is necessary also to note the large mobility of carriers of a charge and their small concentration, sharp anisotropy of many kinetic coefficients. The weak blocking of valiant and free zones that characterizes a half-metal condition allows to operate a mutual arrangement of zones by many influences-magnetic field, pressure, doping by various impurity. The half-metals are rather perspective materials from the point of view of their probable application in various devices. In present time the half-metal alloys BiSb have wide application in thermoelectric generators and refrigerators. They have appeared convenient object for study of distribution of electromagnetic waves in solid-state plasma. The half-metals are also perspective materials for low temperature electronics. In work [1] the opportunity of use of half-metals BiSb with percentage BI and Sb from 8 % up to 25 % was shown as high-sensitivity and of small inertion indicators of UHF radiation where thermoelectric effect is used. The principle of action of such indicators is based on occurrence of a gradient of temperature in a half-metal crystal BiSb that has two contacts of the various square with flowing electrical current. Basic element of such device is the dot contact metal - half-metal. At course of a current of any direction through dot contact the temperature of last one raises owing to large density of a current in contact area while temperature of contact of the large area practically does not change. In result there is a gradient of temperature and appropriate to it thermo-EMF between contacts in a half-metal crystal. It serves a measure of the absorbed capacity by the given device. On the basis of the given model we created indicators of electromagnetic radiation in a wide range of lengths of waves down to millimeter. Theoretically and experimentally its basic characteristics - volt-watt sensitivity, volt-ampere characteristic, inertion and noise (high-frequency and low-frequency) characteristic are described full enough in work [2].
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