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Visnyk of the Lviv University Series Physics

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Published Jan 1, 2024• 0 citations
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Abstract

Entanglement of quantum states of two spin system with XY interaction is examined.The analytical dependence of coherence on the interaction constants of the XY model and its time evolution has been calculated.The quantum protocol has also been developed to compute coherence on a quantum computer.The quantum protocol is based on the relationship between coherence and the average spin value.The protocol was implemented on the AerSimulator.

DOI
10.30970/vph.61.2024.167

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Entanglement of quantum states of two spin system with XY interaction is examined.The analytical dependence of coherence on the interaction constants of the XY model and its time evolution has been calculated.The quantum protocol has also been developed to compute coherence on a quantum computer.The quantum protocol is based on the relationship between coherence and the average spin value.The protocol was implemented on the AerSimulator.
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Abstract The interaction of the XY n‐spin cyclic model with a two‐mode cavity field in the rotating‐wave approximation is investigated in the framework of a generalized Jaynes–Cummings two‐level system consisting of the vacuum state and a thermally averaged manifold of excited sates. Computation of the energy of this manifold allows this interaction to be examined in off‐resonant states. Time evolution of the population inversion, photon distribution, and temperature distribution for an excited initial state are computed via second‐ and third‐order perturbation expansion of the time evolution operator matrix elements for the excited and ground states, respectively and for an ideal squeezed initial coherent state of the cavity field. It was assumed that the two modes have initially the same photon distribution. The pattern of the spin population inversion appears as a manifestation of multiple and complicated inerferences, which is mathematically reflected in a double discrete summation that appears in the calculation of the dynamics. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2008