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arXiv · 2204.02734

Critical quantum thermometry and its feasibility in spin systems

Enes Aybar·Artur Niezgoda·Safoura S. Mirkhalaf·Morgan W. Mitchell·Daniel Benedicto Orenes·Emilia Witkowska
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Abstract

In this work, we study temperature sensing with finite-sized strongly correlated systems exhibiting quantum phase transitions. We use the quantum Fisher information (QFI) approach to quantify the sensitivity in the temperature estimation, and apply a finite-size scaling framework to link this sensitivity to critical exponents of the system around critical points. We numerically calculate the QFI around the critical points for two experimentally-realizable systems: the spin-1 Bose-Einstein condensate and the spin-chain Heisenberg XX model in the presence of an external magnetic field. Our results confirm finite-size scaling properties of the QFI. Furthermore, we discuss experimentally-accessible observables that (nearly) saturate the QFI at the critical points for these two systems.

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Enes Aybar, Artur Niezgoda, Safoura S. Mirkhalaf, Morgan W. Mitchell, Daniel Benedicto Orenes, Emilia Witkowska. 2022-04-06. Critical quantum thermometry and its feasibility in spin systems. https://doi.org/10.22331/q-2022-09-19-808

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