Using a quantum SWAP engine to experimentally validate thermodynamic uncertainty relations

Krishna Shende; Arvind; Kavita Dorai

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arXiv · 2410.16230

Using a quantum SWAP engine to experimentally validate thermodynamic uncertainty relations

Krishna Shende·Arvind·Kavita Dorai

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Abstract

Thermodynamic uncertainty relations (TURs) arise from the bounds on fluctuations of thermodynamics quantities during a non-equilibrium process and they impose constraints on the corresponding process. We experimentally implement a quantum SWAP engine on a nuclear magnetic resonance setup and demonstrate that a Gibbs thermal state can be prepared in two different ways, either directly from a thermal equilibrium state, or by first initializing the system in a pseudopure state. We show that the quantum SWAP engine can work both as a heat engine and as a refrigerator. Starting from a pseudopure state, we construct the SWAP engine, and investigate the violation of two different TURs, namely a generalized TUR and a tighter, more specific TUR. Our results validate that the generalized TUR is obeyed in all the working regimes of the SWAP engine, while the tighter TUR is violated in certain regimes. ~

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Krishna Shende, Arvind, Kavita Dorai. 2024-10-21. Using a quantum SWAP engine to experimentally validate thermodynamic uncertainty relations. https://arxiv.org/abs/2410.16230

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