RF SET 超灵敏静电计

RF single－electron transistor for ultra－sensitive electrometer

摘要: 单电子晶体管（SET）作为灵敏静电计的灵敏度受到噪声的限制，其中散粒噪声（shot noise）是本征噪声，决定着单电子晶体管灵敏度的极限.利用射频(radio frequency, RF)单电子晶体管的极高的工作频率，可以消除SET的1/f噪声，从而达到极限灵敏度.利用一级低温低噪声放大器和一级室温放大器放大工作在反射模式的射频单电子晶体管的输出信号，使用LC共振电路，抬高了SET右边的整个微波系统的阻抗，使之与单电子的输出阻抗匹配，从而提高了RF SET静电计的灵敏度.

Abstract: A single－electron transistor(SET) can be used as a sensitive electrometer whose sensitivity is limi－ted by noise. Shot noise is the intrinsic noise which determines the limit of sensitivity of the SET. Since an RF SET works at a very high frequency, its 1/f noise can be eliminated and thus the limit of sensitivity can be reached. An LC resonant circut is used to increase the characteristic impedance of the microwave system to couple with the output impedance of the SET, and so the sensitivity of the RF SET electrometer is improved.