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arXiv · 2507.23439

Quantum typicality approach to energy flow between two spin-chain domains at different temperatures

Laurenz Beckemeyer·Markus Kraft·Mariel Kempa·Dirk Schuricht·Robin Steinigeweg
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Abstract

We discuss a quantum typicality approach to examine systems composed of two subsystems at different temperatures. While dynamical quantum typicality is usually used to simulate high-temperature dynamics, we also investigate low-temperature dynamics using the method. To test our method, we investigate the energy current between subsystems at different temperatures in various paradigmatic spin-1/2 chains, specifically the XX chain, the critical transverse-field Ising chain, and the XXZ chain. We compare our numerics to existing analytical results and find a convincing agreement for the energy current in the steady state for all considered models and temperatures.

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Laurenz Beckemeyer, Markus Kraft, Mariel Kempa, Dirk Schuricht, Robin Steinigeweg. 2025-07-31. Quantum typicality approach to energy flow between two spin-chain domains at different temperatures. https://doi.org/10.1103/l8qy-hfn5

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