Entanglement generation and enhancement in a two-qubit system by local perturbation

Abstract

Consider a system of two qubits which are coupled to each other. In this paper, it is shown using numerical methods that in order to generate entanglement in a system, either the initial state must not be an eigenvector of a Hamiltonian or a local perturbation must be turned on. Perturbing one qubit increases the chance of maximal entanglement through time and perturbing two qubits increases the period of entanglement.