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Control of Dephasing and Phonon Emission in Coupled Quantum Dots

S. Debald·T. Brandes·B. Kramer
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Abstract

We predict that phonon subband quantization can be detected in the non-linear electron current through double quantum dot qubits embedded into nano-size semiconductor slabs, acting as phonon cavities. For particular values of the dot level splitting $Δ$, piezo-electric or deformation potential scattering is either drastically reduced as compared to the bulk case, or strongly enhanced due to phonon van Hove singularities. By tuning $Δ$ via gate voltages, one can either control dephasing, or strongly increase emission into phonon modes with characteristic angular distributions.

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S. Debald, T. Brandes, B. Kramer. 2002-04-20. Control of Dephasing and Phonon Emission in Coupled Quantum Dots. https://doi.org/10.1103/physrevb.66.041301

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