Document Type : Original Paper
Authors
Department of Physics, Faculty of Science, Shahid Chamran University of Ahvaz, Ahvaz, Islamic Republic of Iran
Abstract
We study entanglement in coherent spin states and several superpositions of multi-qutrit coherent states evolved under the one-axis counter-twisting Hamiltonian in the presence and absence of a magnetic field. Considering a non-entangled multi-qutrit spin coherent state as an initial one, it is found that the entanglement is instigated with an oscillatory behavior in time; however, its average is a decreasing function of the magnetic field. Also, we observe that under this Hamiltonian, the two-qutrit superposed state retains its maximum entanglement with no change, while, the negativity for the three-qutrit superposed state oscillates in time and its average increases in the presence of the magnetic field.
Keywords
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