A cryogenic amplifier for direct measurement of high-frequency signals from a single-electron transistor

Abstract

We have developed a cryogenic voltage amplifier using GaAs metal semiconductor field effect transistors and coupled it to a superconducting single-electron transistor (SET) inside a dilution refrigerator. With this amplifier, we could extend the maximum output frequency of the SET, normally less than a kilohertz, up to 1 MHz. By placing this amplifier off-chip, we could maintain the low SET temperature required for proper SET operation.