Asymmetric two-dimensional electromagnetically induced grating controlled by a vortex field

Abstract

A new theoretical scheme for two-dimensional (2D) electromagnetically induced grating (EIG) is proposed in a three-level $\Xi$-type atomic system. The system is driven by a weak probe field and two position-dependent coupling fields--a 2D standing-wave field and a vortex field. Due to lopsided spatial modulation of the vortex Laguerre-Gaussian field, the weak probe light could be diffracted into different domains and asymmetric 2D EIG is formed. The result shows that the diffraction patterns and efficiency could be effectively modulated by the azimuthal parameter of the vortex field. Also, the system parameters such as the probe field detuning, the intensity of the vortex field, and the interaction length could be used to regulate the diffraction properties of the 2D EIG effectively. The scheme of asymmetric 2D EIG may have some potential application in all-optical information processing and the design of quantum devices.

Electromagnetically induced grating in azimuthal dependent three-level quantum dot system

“…Recent research has looked at the asymmetric and symmetric diffraction patterns in an ensemble of three-level and fourlevel atomic systems utilizing Laguerre-Gaussian (LG) beams [14,25]. It has been discovered that in multi-level atomic systems, the Fraunhofer diffraction pattern depends on both the intensity profile and the OAM of the applied fields [40].…”

Two-dimensional electromagnetically induced grating via phase regulation in a closed-loop four-level atomic system

“…To improve the diffraction efficiency, by achieving high transmittance with large phase modulation, Wan and coworkers put forward several novel phase grating and gain-phase grating models [34][35][36] in different atomic medium. Furthermore, P-T symmetry [37,38], Raman interaction [39], azimuth modulation of vortex field [40,41] are also used to achieve high-efficiency 2D EIG in atomic or quantum well medium. Inspired by these works, we present an efficient scheme to realize 2D EIG in a closed-loop fourlevel atomic system, in which a strong control field and a weak probe field as well as a position-dependent SW field is applied to interact with the atomic system.…”