English

Derivation of Interacting Two-Qubit Dynamics from Spin-Boson Model

Quantum Physics 2023-06-21 v1 Mesoscale and Nanoscale Physics

Abstract

We derive damping equations of motion for interacting two-spin states from a spin-boson model in order to examine qubit dynamics in quantum computers. On the basis of the composite operator method, we develop the Caldeira-Leggett approach for open quantum systems so that the entanglement dynamics originated from the two-spin correlation can be taken. We demonstrate numerical results for time dependence on the two-spin dynamics. We find that the relaxation of the total spin is described by a quantum version of the Landau-Lifshitz-Gilbert equation for magnetic materials. We also find that a two-spin composite mode keeps oscillation even after the total spin has been fully relaxed. We thus conclude that the two-spin correlation due to the presence of the composite mode is stable against dissipation. We consider the mechanism of why the correlation is maintained.

Keywords

Cite

@article{arxiv.2211.02490,
  title  = {Derivation of Interacting Two-Qubit Dynamics from Spin-Boson Model},
  author = {Hiroaki Matsueda and Yukiya Ide and Sadamichi Maekawa},
  journal= {arXiv preprint arXiv:2211.02490},
  year   = {2023}
}

Comments

6 pages, 1 figure, accepted for publication to JPSJ Conf. Series (LT29 proceedings)

R2 v1 2026-06-28T05:11:45.857Z