2007/08/18 by Hua Qin, David A. Williams, Qin, Hua +1 · 1 citation
Physics and Astronomy · #FOS: Physical sciences #Mesoscale and Nanoscale Physics (cond-mat.mes-hall) #cond-mat.mes-hall
paper · pdf · doi:10.48550/arxiv.0708.2473
11 pages, 3 figures. This article is identical to the version that appeared in Appl. Phys. Lett. 88, 203506 (2006). The published version can be found at http://apl.aip.org/
arxiv created 2007/08/18 · arxiv updated 2009/12/01
We fabricate and characterize a radio-frequency semiconductor point-contact electrometer (RF-PC) analogous to radio-frequency single-electron transistors [RF-SETs, see Science \bf 280, 1238 (1998)]. The point contact is formed by surface Schottky gates in a two-dimensional electron gas (2DEG) in an AlGaAs/GaAs heterostructure. In the present setup, the PC is operating as a simple voltage-controlled resistor rather than a quantum point contact (QPC) and demonstrates a charge-sensitivity about 2× 10-1 e/√(Hz) at a bandwidth of 30 kHz without the use of a cryogenic RF preamplifier. Since the impedance of a typical point-contact device is much lower than the impedance of the typical SET, a semiconductor-based RF-PC, equipped with practical cryogenic RF preamplifiers, could realize an ultra-fast and ultra-sensitive electrometer.