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arXiv · 1305.5982

Stimulated Phonon Emission in a Driven Double Quantum Dot

J. I. Colless·X. G. Croot·T. M. Stace·A. C. Doherty·S. D. Barrett·H. Lu·A. C. Gossard·D. J. Reilly
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Abstract

The compound semiconductor gallium arsenide (GaAs) provides an ultra-clean platform for storing and manipulating quantum information, encoded in the charge or spin states of electrons confined in nanostructures. The absence of inversion symmetry in the zinc-blende crystal structure of GaAs however, results in strong piezoelectric coupling between lattice acoustic phonons and electrons, a potential hindrance for quantum computing architectures that can be charge-sensitive during certain operations. Here we examine phonon generation in a GaAs double dot, configured as a single- or two-electron charge qubit, and driven by the application of microwaves via surface gates. In a process that is a microwave analog of the Raman effect, stimulated phonon emission is shown to produce population inversion of a two-level system and provides spectroscopic signatures of the phononic environment created by the nanoscale device geometry.

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J. I. Colless, X. G. Croot, T. M. Stace, A. C. Doherty, S. D. Barrett, H. Lu, A. C. Gossard, D. J. Reilly. 2013-05-26. Stimulated Phonon Emission in a Driven Double Quantum Dot. https://doi.org/10.1038/ncomms4716

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