Using Polarons for sub-nK Quantum Nondemolition Thermometry in a Bose-Einstein Condensate.

  title={Using Polarons for sub-nK Quantum Nondemolition Thermometry in a Bose-Einstein Condensate.},
  author={Mohammad Mehboudi and Aniello Lampo and Christos Charalambous and Luis A. Correa and Miguel Angel Garcia-March and Maciej Lewenstein},
  journal={Physical review letters},
  volume={122 3},
We introduce a novel minimally disturbing method for sub-nK thermometry in a Bose-Einstein condensate (BEC). Our technique is based on the Bose polaron model; namely, an impurity embedded in the BEC acts as the thermometer. We propose to detect temperature fluctuations from measurements of the position and momentum of the impurity. Crucially, these cause minimal backaction on the BEC and hence, realize a nondemolition temperature measurement. Following the paradigm of the emerging field of… 

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