2018/06/30 by Mohammad Mehboudi, Aniello Lampo, Christos Charalambous +4 · 1 citation
Computer Science · Physics and Astronomy · #Advanced Thermodynamics and Statistical Mechanics #Bose–Einstein condensate #Boson #Cold Atom Physics and Bose-Einstein Condensates #Dissipative system #Electron #Momentum (technical analysis) #Physics #Polaron #Quantum #Quantum Information and Cryptography #Quantum electrodynamics #Quantum mechanics #Statistical physics #cond-mat.quant-gas #cond-mat.stat-mech #quant-ph
paper · pdf · doi:10.1103/physrevlett.122.030403
published as Phys. Rev. Lett. 122, 030403 (2019) · New references added
arxiv created 2018/07/01 · openalex publication_date 2019/01/24 · arxiv updated 2019/01/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
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 quantum thermometry, we combine tools from quantum parameter estimation and the theory of open quantum systems to solve the problem in full generality. We thus avoid any simplification, such as demanding thermalization of the impurity atoms, or imposing weak dissipative interactions with the BEC. Our method is illustrated with realistic experimental parameters common in many labs, thus showing that it can compete with state-of-the-art destructive techniques, even when the estimates are built from the outcomes of accessible (suboptimal) quadrature measurements.