Quantum coherence induced by magnons

• URL: http://arxiv.org/abs/2509.17332v1
• Date: Mon, 22 Sep 2025 03:08:58 GMT
• Title: Quantum coherence induced by magnons
• Authors: V. C. Vieira, F. M. de Paula,
• Abstract summary: We analyze quantum coherence generated by non-interacting magnons in a ferromagnetic spin chain described by the isotropic Heisenberg model.<n>We introduce coherence-based definitions of entropy, temperature, and heat capacity, establishing a formal analogy with standard thermodynamic quantities.
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: We analyze quantum coherence generated by non-interacting magnons in a ferromagnetic spin chain described by the isotropic Heisenberg model. The exact expression derived for the reduced density operator of an arbitrary subsystem reveals that single-site coherence vanishes, while maximal coherence arises in a pure single-mode magnon state. Remarkably, this maximum depends solely on the number of coherently superposed microstates. Based on this property, we introduce coherence-based definitions of entropy, temperature, and heat capacity, establishing a formal analogy with standard thermodynamic quantities.

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