Cavity-spin-orbit competition in quantum dot systems under a magnetic field

Abstract

In this work we accomplish a exhaustive study about few particle and many-body systems under a perpendicular magnetic field and spin-orbit coupling inside a quantum electrodynamics cavity, whose analysis has so far not been treated in such detail. In fact, the interactions arising from these phenomena are interpreted by means of detecting rotating and antirotating terms between radiation and matter. In a single-electron quantum dot, we identify spin transitions that can be modified by cavity coupling strength with circularly polarized light using numerical calculations. As a result of spin-radiation relations, the Zeeman effect is countered by forbidden transitions that prefer spin "up" or "down". Therefore, the cavity-spin-orbit competition results in spin-field transitions in the ground state. Such transitions, which are connected to shifts in spin dominance, are predicted by a quasianalytic computation of an effective Landé factor that depends on the degree of coupling between the cavity and the magnetic field. In the system with two interacting electrons in quantum dot, we demonstrate that the cavity only couples, in dipolar approximation, to the center of mass coordinates. However, this coupling leads to slight variation in the single-electron density and spin fields cause by the interaction with radiation. In addition, a variation in the density of Bell spin states is perceived. Based on the above results, we suggest applications such as the construction of switches in spintronics and quantum information processing systems, as well as measurements by nuclear magnetic resonance. Finally, some insides in the future work are introduced, with the aim of extend our research to many body cases and go beyond to the dipolar approximation