arXiv:cond-mat/0302085 · Journal of Applied Physics

Development and operation of the twin radio frequency single electron transistor for cross-correlated charge detection

Tilo M. Buehler, D. J. Reilly, R.P. Starrett, Nadia Court, A. R. Hamilton, Andrew S. Dzurak, Robert G. Clark

Published Oct 4, 2004• 23 citations

Abstract

Ultrasensitive detectors and readout devices based on the radio frequency single electron transistor (rf-SET) combine near quantum-limited sensitivity with fast operation. Here we describe a twin rf-SET detector that uses two superconducting rf-SETs to perform fast, real-time cross-correlated measurements in order to distinguish subelectron signals from charge noise on microsecond time scales. The twin rf-SET makes use of two tuned resonance circuits to simultaneously and independently address both rf-SETs using wavelength division multiplexing and a single cryogenic amplifier. We focus on the operation of the twin rf-SET as a charge detector and evaluate the cross talk between the two resonance circuits. Real-time suppression of charge noise is demonstrated by cross correlating the signals from the two rf-SETs. For the case of simultaneous operation, the rf-SETs had charge sensitivities of δqSET1=7.5μe∕Hz and δqSET2=4.4μe∕Hz.

DOI: 10.1063/1.1786671

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