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arXiv · 1405.2261

Sub-Kelvin optical thermometry of an electron reservoir coupled to a self-assembled InGaAs quantum dot

F. Seilmeier·M. Hauck·E. Schubert·G. J. Schinner·S. E. Beavan·A. Högele
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Abstract

We show how resonant laser spectroscopy of the trion optical transitions in a self-assembled quantum dot can be used to determine the temperature of a nearby electron reservoir. At finite magnetic field the spin-state occupation of the Zeeman-split quantum dot electron ground states is governed by thermalization with the electron reservoir via co-tunneling. With resonant spectroscopy of the corresponding excited trion states we map out the spin occupation as a function of magnetic field to establish optical thermometry for the electron reservoir. We demonstrate the implementation of the technique in the sub-Kelvin temperature range where it is most sensitive, and where the electron temperature is not necessarily given by the cryostat base temperature.

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F. Seilmeier, M. Hauck, E. Schubert, G. J. Schinner, S. E. Beavan, A. Högele. 2014-05-09. Sub-Kelvin optical thermometry of an electron reservoir coupled to a self-assembled InGaAs quantum dot. https://doi.org/10.1103/physrevapplied.2.024002

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