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arXiv · 2509.17356

The Free Energy Barrier: An Eyring-Polanyi bound for stabilizer Hamiltonians, with applications to quantum error correction

Nouédyn Baspin
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Abstract

The lack of an energy barrier in stabilizer Hamiltonians is well known to be an indication of short thermalisation times; and serves as a simple criteria to rule out self-correction. Its applicability has recently been challenged by the discovery of stabilizer codes with maximal energy barriers whose self-correcting status remains unclear. We address this question by introducing the more general notion of a free energy barrier, whose absence is also demonstrated to guarantee fast thermalisation. Applying these new results to the Layer codes, we prove that they lack self-correction.

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Nouédyn Baspin. 2025-09-22. The Free Energy Barrier: An Eyring-Polanyi bound for stabilizer Hamiltonians, with applications to quantum error correction. https://arxiv.org/abs/2509.17356

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