L. DiCarlo, Y. Zhang, D. T. McClure, C. M. Marcus, L. N. Pfeiffer, K. W. West
Published 2006-04-02, updated 2006-06-09Version 2
We describe the construction and operation of a two-channel noise detection system for measuring power and cross spectral densities of current fluctuations near 2 MHz in electronic devices at low temperatures. The system employs cryogenic amplification and fast-Fourier-transform based spectral measurement. The gain and electron temperature are calibrated using Johnson noise thermometry. Full shot noise of 100 pA can be resolved with an integration time of 10 s. We report a demonstration measurement of bias-dependent current noise in a gate defined GaAs/AlGaAs quantum point contact.
Comments: related papers at http://marcuslab.harvard.edu
Journal: Rev. Sci. Instru. 77, 073906 (2006).
Mechanisms of Decoherence at Low Temperatures
Decoherence in Disordered Conductors at Low Temperatures, the effect of Soft Local Excitations
Energy dependence of current noise in superconducting/normal metal junctions
