Quantum Information and Computation

Quantum fidelity evolution of Penning trap coherent states in an asymmetric open quantum system

Somayeh Mehrabankar, Davood Afshar, Mojtaba Jafarpour

Published May 1, 2019• 0 citations

Abstract

Assuming the Born-Markov approximation, we study the evolution of quantum fidelity in asymmetric systems consisting of two and three-mode independent oscillators interacting with a thermal bath. To this end, considering the Penning trap coherent states as the initial states of the system, we have studied the evolution of the quantum fidelity as a function of the parameters of the system, the environment and the initial state, in the framework of open systems theory. It is observed that fidelity is a decreasing function of the temperature and dissipation coefficient for both two and three-mode states. However, for the two-mode state, the fidelity is an oscillating function of time but a decreasing one in the low values of the magnetic field. In the case of a three-mode state, although the fidelity decreases with the magnetic field, dissipation coefficient and temperature, it is an irregular function of the asymmetric coefficient.

DOI: 10.26421/qic19.5-6-3

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