Magnetoelectric polarizability of a multiferroic antiferromagnetic quantum spin system: The influence of both the site-dependent magnetic and electric fields

Abstract

In the present issue, the magnetoelectric effect in a multiferroic antiferromagnetic spin system with the Dzyaloshinskii Moriya interaction is investigated. The Dzyaloshinskii Moriya interaction is assimilated to a local electric polarization coupled to an electric field which is a site-dependent field as well as the applied external magnetic field. By using the spin-wave theory as a diagonalization method and via the partition function, the physical properties of the system such as magnetoelectric polarizability, magnetization, and electric polarization are obtained. The numerical results reveal that the site-dependent magnetic and electric fields play a remarkable role in the quantum phase transition phenomena that occur in our system. In fact, the magnetoelectric properties response of the system due to the change of the temperature or the external fields reveals the formation of the intermediate states tuneable by the site-dependent parameters. Furthermore, the electric polarization and the magnetoelectric polarizability response of the system due to the variation of the magnetic field show that the magnetoelectric effect can be control by varying the magnetic or/and the electric site-dependent parameter. Overall, the cumulative influence of the site-dependent magnetic and electric fields is a good strategy to detect, elucidate, and control the unconventional phases transition that undergoes a multiferroic antiferromagnetic quantum spin system. Moreover, the results obtained in this work are very interesting for the technological application point of view because there could provide a new prescription for the construction of multifunctional spintronic devices.