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arXiv · 2305.03967

Quantum Energy Teleportation and Entropy Change due to Feedback Control in One-Dimensional Heisenberg Model

Kanji Itoh·Yusuke Masaki·Hiroaki Matsueda
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Abstract

We study the quantum energy teleportation in a four-spin one-dimensional Heisenberg model. A local magnetic field is applied at the edge sites to control the degree of the ground-state entanglement. In the teleportation protocol, an energy sender performs a projective measurement at one edge site, while an energy receiver performs a feedback control at the other edge site dependent on the measurement result to extract energy. We find that the energy extracted by the receiver takes a maximum at intermediate value of the local magnetic field. We also find that this magnetic-field behavior is almost proportional to entropy changes due to the feedback control. The role of a feedback control in an entropy change is discussed in terms of entanglement thermodynamics.

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Kanji Itoh, Yusuke Masaki, Hiroaki Matsueda. 2023-05-06. Quantum Energy Teleportation and Entropy Change due to Feedback Control in One-Dimensional Heisenberg Model. https://arxiv.org/abs/2305.03967

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