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arXiv · 2408.06418

Heat as a witness of quantum properties

A. de Oliveira Junior·Jonatan Bohr Brask·Patryk Lipka-Bartosik
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Abstract

We present a new approach for witnessing quantum resources, such as entanglement and coherence, based on heat generation. Inspired by Maxwell's demon, we ask what the optimal heat exchange between a quantum system and a thermal environment is when the process is assisted by a quantum memory. We derive fundamental energy constraints in this scenario and show that quantum states can reveal non-classical signatures via heat exchange. This approach leads to a heat-based witness for quantum properties, offering an alternative to system-specific measurements, as it only relies on fixed energy measurements in a thermal ancilla. We illustrate our findings with the detection of entanglement in isotropic states and coherence in two-spin systems interacting with a single-mode electromagnetic field.

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A. de Oliveira Junior, Jonatan Bohr Brask, Patryk Lipka-Bartosik. 2024-08-12. Heat as a witness of quantum properties. https://doi.org/10.1103/physrevlett.134.050401

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