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arXiv · 1305.6881

A non-invasive electron thermometer based on charge sensing of a quantum dot

A. Mavalankar·S. J. Chorley·J. Griffiths·G. A. C. Jones·I. Farrer·D. A. Ritchie·C. G. Smith
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Abstract

We present a thermometry scheme to extract the temperature of a 2DEG by monitoring the charge occupation of a weakly tunnel-coupled 'thermometer' quantum dot using a quantum point contact detector. Electronic temperatures between 97 mK and 307 mK are measured by this method with an accuracy of up to 3 mK, and agree with those obtained by measuring transport through a quantum dot. The thermometer does not pass a current through the 2DEG, and can be incorporated as an add-on to measure the temperature simultaneously with another operating device. Further, the tuning is independent of temperature.

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A. Mavalankar, S. J. Chorley, J. Griffiths, G. A. C. Jones, I. Farrer, D. A. Ritchie, C. G. Smith. 2013-05-29. A non-invasive electron thermometer based on charge sensing of a quantum dot. https://doi.org/10.1063/1.4823703

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