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arXiv · 2503.06103

Study of double kicked top: a classical and quantum perspective

Avadhut V. Purohit·Udaysinh T. Bhosale
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Abstract

We study the double kicked top (DKT), which is an extension of the standard quantum kicked top (QKT) model. The model allows us to study the transition from time-reversal symmetric to broken time-reversal symmetric dynamics. Our transformation in the kick strength parameter space $(k, k') \to (k_r, k_θ)$ reveals interesting features. The transformed kicked strength parameter $k_r$ drives a higher growth of chaos and is equivalent to the standard QKT, whereas the other transformed kicked strength parameter $k_θ$ leads to a weaker growth. We discuss the fixed points, their stability, and verify results obtained by computing the largest Lyapunov exponent (LLE) and the Kolmogorov-Sinai entropy (KSE). We exactly solve 2- to 4-qubit versions of DKT by obtaining its eigenvalues, eigenvectors and the entanglement dynamics. Furthermore, we find the criteria for periodicity of the entanglement dynamics. We investigate measures of quantum correlations from two perspectives: the deep quantum and the semi-classical regime. Signatures of phase-space structure are numerically shown in the long-time averages of the quantum correlations. Our model can be realised experimentally as an extension of the standard QKT.

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Avadhut V. Purohit, Udaysinh T. Bhosale. 2025-07-08. Study of double kicked top: a classical and quantum perspective. https://doi.org/10.1103/w9ml-jt9c

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