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arXiv · cond-mat/0411468

Nonadiabatic Electron Manipulation in Quantum-Dot Arrays

Keiji Saito·Yosuke Kayanuma
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Abstract

A novel method of coherent manipulation of the electron tunneling in quantum-dots is proposed, which utilizes the quantum interference in nonadiabatic double-crossing of the discrete energy levels. In this method, we need only a smoothly varying gate voltage to manipulate electrons, without a sudden switching-on and off. A systematic design of a smooth gate-pulse is presented with a simple analytic formula to drive the two-level electronic state to essentially arbitrary target state, and numerical simulations for complete transfer of an electron is shown for a coupled double quantum-dots and an array of quantum-dots. Estimation of the manipulation-time shows that the present method can be employed in realistic quantum-dots.

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Keiji Saito, Yosuke Kayanuma. 2004-11-18. Nonadiabatic Electron Manipulation in Quantum-Dot Arrays. https://doi.org/10.1103/physrevb.70.201304

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