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Adiabatic Transfer of Electrons in Coupled Quantum Dots

T. Brandes·T. Vorrath
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Abstract

We investigate the influence of dissipation on one- and two-qubit rotations in coupled semiconductor quantum dots, using a (pseudo) spin-boson model with adiabatically varying parameters. For weak dissipation, we solve a master equation, compare with direct perturbation theory, and derive an expression for the `fidelity loss' during a simple operation that adiabatically moves an electron between two coupled dots. We discuss the possibility of visualizing coherent quantum oscillations in electron `pump' currents, combining quantum adiabaticity and Coulomb blockade. In two-qubit spin-swap operations where the role of intermediate charge states has been discussed recently, we apply our formalism to calculate the fidelity loss due to charge tunneling between two dots.

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T. Brandes, T. Vorrath. 2002-07-10. Adiabatic Transfer of Electrons in Coupled Quantum Dots. https://doi.org/10.1103/physrevb.66.075341

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