Trading athermality for nonstabilizerness
Phys. Rev. A 113, 052421 – Published 11 May, 2026
DOI: https://doi.org/10.1103/hwfq-ytkb
Abstract
Quantum advantage arises from quantum states that cannot be efficiently simulated on a classical computer. Such states are characterized by a property known as nonstabilizerness. In this work, we investigate whether nonstabilizerness can be generated by placing an initially stabilizer state in contact with a heat bath. Under minimal thermodynamic assumptions, we derive a necessary and sufficient condition for when this is possible. This yields an analytic characterization of all nonstabilizer qubit states reachable through such thermal processes, together with explicit bounds on their nonstabilizerness. This, in turn, allows us to identify optimal regimes for generating this resource, including the Hamiltonians that maximize nonstabilizerness and the critical temperatures at which it emerges. Beyond the qubit case, we establish a general trade-off between the nonstabilizerness attainable under thermal operations and the initial nonequilibrium free energy of the system.
