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arXiv · 1305.2309

Enhanced photocurrent readout for a quantum dot qubit by bias modulation

J. H. Quilter·R. J. Coles·A. J. Ramsay·A. M. Fox·M. S. Skolnick
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Abstract

We demonstrate coherent control of a quantum dot exciton using photocurrent detection with a sinusoidal reverse bias. Optical control is performed at low bias, where tunneling-limited coherence times are long. Following this step, the tunneling rates are increased to remove the long-lived hole, achieving a high photocurrent signal. For a detection efficiency of 68%, electron and hole tunneling times during optical control of 200 ps and 20 ns can be achieved, compared to 120 ps and 7 ns for the constant bias case, respectively.

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J. H. Quilter, R. J. Coles, A. J. Ramsay, A. M. Fox, M. S. Skolnick. 2013-05-10. Enhanced photocurrent readout for a quantum dot qubit by bias modulation. https://doi.org/10.1063/1.4804373

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