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arXiv · 1207.2972

Coherent Adiabatic Spin Control in the Presence of Charge Noise Using Tailored Pulses

Hugo Ribeiro·Guido Burkard·J. R. Petta·H. Lu·A. C. Gossard
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Abstract

We study finite-time Landau-Zener transitions at a singlet-triplet level crossing in a GaAs double quantum dot, both experimentally and theoretically. Sweeps across the anticrossing in the high driving speed limit result in oscillations with a small visibility. Here we demonstrate how to increase the oscillation visibility while keeping sweep times shorter than T2* using a tailored pulse with a detuning dependent level velocity. Our results show an improvement of a factor ~2.9 for the oscillation visibility. In particular, we were able to obtain a visibility of ~0.5 for St\"uckelberg oscillations, which demonstrates the creation of an equally weighted superposition of the qubit states.

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Hugo Ribeiro, Guido Burkard, J. R. Petta, H. Lu, A. C. Gossard. 2012-07-12. Coherent Adiabatic Spin Control in the Presence of Charge Noise Using Tailored Pulses. https://doi.org/10.1103/physrevlett.110.086804

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