Extra-low power consumption amplifier based on HEMT in unsaturated mode for use at subkelvin ambient temperatures

A new approach to deep-cooled amplifier design with microwatt level consumed/dissipated power is presented. The relevant technique is based on exploiting the unsaturated regime of the high electron mobility transistor. The power consumption of several microwatts for 20 dB gain amplifier was obtained at 300 mK ambient temperature. This is at least an order of magnitude better than the figures known up to date for high-frequency (0.1-1 GHz) amplifiers.