The gaussistor, a solid state electronic valve

The property of magnetoresistivity can be employed to produce tuned amplifiers and oscillators principally for the sub-audio and possibly for the audio range. To accomplish this, a strip or a coil of a magnetoresistive material, such as bismuth, is placed in the magnetic circuit of a laminated or a ferrite core of an inductor and appropriately wired into an electric circuit containing a dc power supply. The circuitry is simple and the device can be constructed to match a wide range of input and output impedances. The recently developed semiconductor indium antimonide, having an exceptionally high magnetoresistive coefficient, offers hope of obtaining useful power gain at room temperature. The basic theoretical concepts are presented and experimental results with bismuth and indium antimonide are given.