Design of cryogenic 700 MHz amplifier Original Research Article

We present a way to design a high-frequency low-temperature balanced amplifier. The design is based on measured cryogenic scattering-parameters combined with a small-signal noise model. Using the design process we constructed an amplifier that was measured to have a gain of 16 dB and a noise temperature of ∼3 K when cooled to 4.2 K.