Radio-frequency single-electron transistor: Toward the shot-noise limit

We have fabricated an aluminum single-electron transistor and characterized it at frequencies up to 10 MHz by measuring the reflected signal from a re sonant tank in which the transistor is embedded. We measured the charge sen sitivity of this radio-frequency single-electron transistor to be 3.2x10(-6 ) e/root Hz, which corresponds to the uncoupled energy sensitivity of 4.8 ( h) over bar. Our measurements indicate that with further improvements, the radio-frequency single-electron transistor could reach the shot-noise limit estimated to be about 1 (h) over bar. (C) 2001 American Institute of Physi cs.