Single-electron counting statistics with a finite frequency bandwidth

Abstract

Single-electron counting is widely used to probe single electron dynamics and correlated electron transport through quantum dots. However, finite frequency bandwidth in amplifying and analyzing the detector current removes fast counting events and alters the statistics. We have developed a correction scheme to obtain the actual tunneling rates through a quantum dot, when the detector has a low pass filter with a cutoff frequency comparable to the rates. The accuracy of our scheme is confirmed by simulating the filtering effect on Poisson random switching events and by applying it to experimental data for self-checking.

Spin-dependent tunneling rates for electrostatically defined GaAs quantum dots

“…The effect of the finite frequency bandwidth for charge detection was carefully corrected by considering undetected events under the Poisson process [28]. First, we chose the detection bandwidth to obtain a high signal-to-noise ratio, as shown in the inset of Fig.…”

“…Such missing events for the empty (occupied) state affect the measurement of the dwell time for the occupied (empty) state. We developed a correction scheme for a first-order low-pass filter [28]. The tunneling rates in this work were obtained by using this scheme with a filtering time constant τ = 60 μs and hysteretic thresholds.…”

Time-dependent shot noise in multi-level quantum dot-based single-electron devices

“…If the ability of SET to provide a fine control of current due to Coulomb blockade is known since the late 1980s [7][8][9][10], it is only recently that experimental Silicon quantum dot (QD)based SETs, likely to be integrated in silicon electronics, have shown good Coulomb-blockade oscillations at room temperature [11][12][13][14][15]. In the meantime, detection of single-electron events in devices has been performed experimentally, allowing measurements of SN and higher order correlation functions, mostly using a quantum point contact [16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32].…”