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

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 نشر من قبل Aquila Mavalankar
 تاريخ النشر 2013
  مجال البحث فيزياء
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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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