Hall-effect reinforcement of high-frequency fields in semiconductors

The paper considers a number of high-frequency applications of a technique, described by Midgley, which uses Hall effect in a semiconductor to increase the penetration of an externally applied magnetic field. High-mobility semiconductors, like the intermetallic indium compounds, giving large Hall effects, also have a high conductivity with a correspondingly small skin depth, so that it becomes difficult to utilise the body of the semiconductor effectively. Hall-effect reinforcement of the applied field is therefore particularly valuable at high frequencies, and methods by which this may be exploited to advantage in Hall-effect and magnetoresistance-effect linear mixers, power-measuring devices and mode transducers, are discussed. A new form of electrically controlled attenuator embodying the same principle is also proposed.