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arXiv · 2504.11664

Work Statistics and Quantum Trajectories: No-Click Limit and non-Hermitian Hamiltonians

Manali Malakar·Alessandro Silva
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Abstract

We investigate quantum work statistics within the standard two-point measurement (TPM) scheme in continuously monitored quantum systems, including the effects of generalized unitary evolution, possibly controlled by quantum circuit models, and multiple generalized measurements as well as post-selection of no-click trajectories. We derive an explicit expression for the work generating function that naturally incorporates non-Hermitian dynamics arising from quantum jump processes and reveals deviations from the standard Jarzynski equality due to measurement-induced asymmetries. We illustrate our theoretical framework by analyzing a one-dimensional transverse-field Ising model under local spin monitoring. In this model, increased measurement strength projects the system onto the no-click state, leading to a suppression of energy fluctuations and measurement-induced energy saturation, reminiscent of the quantum Zeno effect. Moreover, we find signatures of the measurement-induced transition observed in the no-click limit in the moments of the work distribution.

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Manali Malakar, Alessandro Silva. 2025-04-15. Work Statistics and Quantum Trajectories: No-Click Limit and non-Hermitian Hamiltonians. https://doi.org/10.1103/2nqj-dvqk

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