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arXiv · 2103.13730

Hidden symmetry in the biased Dicke model

Xilin Lu·Zi-Min Li·Vladimir V. Mangazeev·Murray T. Batchelor
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Abstract

The symmetry operators generating the hidden $\mathbb{Z}_2$ symmetry of the asymmetric quantum Rabi model (AQRM) at bias $\epsilon \in \frac{1}{2}\mathbb{Z}$ have recently been constructed by V. V. Mangazeev et al. [J. Phys. A: Math. Theor. 54 12LT01 (2021)]. We start with this result to determine symmetry operators for the $N$-qubit generalisation of the AQRM, also known as the biased Dicke model, at special biases. We also prove for general $N$ that the symmetry operators, which commute with the Hamiltonian of the biased Dicke model, generate a $\mathbb{Z}_2$ symmetry.

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Xilin Lu, Zi-Min Li, Vladimir V. Mangazeev, Murray T. Batchelor. 2021-03-25. Hidden symmetry in the biased Dicke model. https://doi.org/10.1088/1751-8121%2Fac0f16

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