Quantum dot state initialization by control of tunneling rates

Abstract

We study the loading of electrons into a quantum dot with dynamically controlled tunnel barriers. We introduce a method to measure tunneling rates for individual discrete states and to identify their relaxation paths. Exponential selectivity of the tunnel coupling enables loading into specific quantum dot states by tuning independently energy and rates. While for the single-electron case orbital relaxation leads to fast transition into the ground state, for electron pairs triplet-to-singlet relaxation is suppressed by long spin-flip times. This enables the fast gate-controlled initialization of either a singlet or a triplet electron pair state in a quantum dot with broad potential applications in quantum technologies.

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Cited by in corpus (5)

• Large twisting angles in Bilayer graphene Moire quantum dot structures
• Non-adiabatic single-electron pump in a dopant-free GaAs/AlGaAs 2DEG
• Spectroscopy of hot-electron pair emission from a driven quantum dot
• Controlling the error mechanism in a tunable-barrier non-adiabatic charge pump by dynamic gate compensation
• Study of Microwave Assisted CNOT Gate