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arXiv · 1405.1981

A single quantum dot as an optical thermometer for mK temperatures

Florian Haupt·Atac Imamoglu·Martin Kroner
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Abstract

Resonant laser spectroscopy of a negatively charged self-assembled quantum dot is utilized to measure the temperature of a three dimensional fermionic reservoir down to 100mK. With a magnetic field applied to the quantum dot the single charged ground state is split by the Zeeman energy. As the quantum dot is in tunnel contact with a thermal electron reservoir, a thermal occupation of the quantum dot spin states is enforced by co-tunneling processes. Resonant laser induced fluorescence is used in order to measure the thermal quantum dot spin state population.

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Florian Haupt, Atac Imamoglu, Martin Kroner. 2014-05-08. A single quantum dot as an optical thermometer for mK temperatures. https://doi.org/10.1103/physrevapplied.2.024001

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