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Fidelity optimization for holonomic quantum gates in dissipative environments

Daniele Parodi·Maura Sassetti·Paolo Solinas·Paolo Zanardi·Nino Zanghi
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Abstract

We analyze the performance of holonomic quantum gates in semi-conductor quantum dots, driven by ultrafast lasers, under the effect of a dissipative environment. In agreement with the standard practice, the environment is modeled as a thermal bath of oscillators linearly coupled with the excitonic states of the quantum dot. Standard techniques of quantum dissipation make the problem amenable to a numerical treatment and allow to determine the fidelity (the common gate-performance estimator), as a function of all the relevant physical parameters. As a consequence of our analysis, we show that, by varying in a suitable way the controllable parameters, the disturbance of the environment can be (approximately) suppressed, and the performance of the gate optimized--provided that the thermal bath is purely superhomic. We conclude by showing that such an optimization it is impossible for ohmic environments.

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Daniele Parodi, Maura Sassetti, Paolo Solinas, Paolo Zanardi, Nino Zanghi. 2006-05-26. Fidelity optimization for holonomic quantum gates in dissipative environments. https://doi.org/10.1103/physreva.73.052304

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