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arXiv · 1505.06172

An Optical Spin Read-out Method for a Quantum Dot using the AC Stark Effect

Edward B. Flagg·Glenn S. Solomon
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Abstract

We propose a method to read-out the spin-state of an electron in a quantum dot in a Voigt geometry magnetic field using cycling transitions induced by the AC Stark effect. We show that cycling transitions can be made possible by a red-detuned, circularly-polarized laser, which modifies the spin eigenstates and polarization selection rules via the AC Stark effect. A Floquet-Liouville supermatrix approach is used to calculate the time-evolution of the density matrix under the experimental conditions of a spin read-out operation. With an overall detection efficiency of 2.5%, the read-out is a single-shot measurement with a fidelity of 76.2%.

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Edward B. Flagg, Glenn S. Solomon. 2015-05-22. An Optical Spin Read-out Method for a Quantum Dot using the AC Stark Effect. https://doi.org/10.1103/physrevb.92.245309

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