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arXiv · 0912.5401

Pulsed Nuclear Pumping and Spin Diffusion in a Single Charged Quantum Dot

Thaddeus D. Ladd·David Press·Kristiaan De Greve·Peter L. McMahon·Benedikt Friess·Christian Schneider·Martin Kamp·Sven Hoefling·Alfred Forchel·Yoshihisa Yamamoto
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Abstract

We report the observation of a feedback process between the nuclear spins in a single charged quantum dot and its trion transition, driven by a periodic sequence of optical pulses. The pulse sequence intersperses off-resonant ultrafast pulses for coherent electron-spin rotation and resonant narrow-band optical pumping. The feedback manifests as a hysteretic triangle-like pattern in the free-induction-decay of the single spin. We present a simple, quasi-analytic numerical model to describe this observation, indicating that the feedback process results from the countering effects of optical nuclear pumping and nuclear spin-diffusion inside the quantum dot. This effect allows dynamic tuning of the electron Larmor frequency to a value determined by the pulse timing, potentially allowing more complex coherent control operations.

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Thaddeus D. Ladd, David Press, Kristiaan De Greve, Peter L. McMahon, Benedikt Friess, Christian Schneider, Martin Kamp, Sven Hoefling, Alfred Forchel, Yoshihisa Yamamoto. 2009-12-30. Pulsed Nuclear Pumping and Spin Diffusion in a Single Charged Quantum Dot. https://doi.org/10.1103/physrevlett.105.107401

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