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arXiv · 2302.13759

Work statistics, quantum signatures and enhanced work extraction in quadratic fermionic models

Alessandro Santini·Andrea Solfanelli·Stefano Gherardini·Mario Collura
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Abstract

In quadratic fermionic models we determine a quantum correction to the work statistics after a sudden and a time-dependent driving. Such a correction lies in the non-commutativity of the initial quantum state and the time-dependent Hamiltonian, and is revealed via the Kirkwood-Dirac quasiprobability (KDQ) approach to two-times correlators. Thanks to the latter, one can assess the onset of non-classical signatures in the KDQ distribution of work, in the form of negative and complex values that no classical theory can reveal. By applying these concepts on the one-dimensional transverse-field Ising model, we relate non-classical behaviours of the KDQ statistics of work in correspondence of the critical points of the model. Finally, we also prove the enhancement of the extracted work in non-classical regimes where the non-commutativity takes a role.

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Alessandro Santini, Andrea Solfanelli, Stefano Gherardini, Mario Collura. 2023-02-27. Work statistics, quantum signatures and enhanced work extraction in quadratic fermionic models. https://doi.org/10.1103/physrevb.108.104308

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