Optically induced diffraction gratings based on periodic modulation of linear and nonlinear effects for atom-light coupling quantum systems near plasmonic nanostructures

Abstract

We investigate the quantum linear and nonlinear effects in a novel five-level quantum system placed near a plasmonic nanostructure. Such a quantum scheme contains a double-V-type subsystem interacting with a weak probe field. The double-V-subsystem is then coupled to an excited state by a strong coupling field, which can be a position-dependent standing-wave field. We start by analyzing the first-order linear as well as the third and fifth order nonlinear terms of the probe susceptibility by systematically solving the equations for the matter-fields. When the quantum system is near the plasmonic nanostructure, the coherent control of linear and nonlinear susceptibilities becomes inevitable, leading to vanishing absorption effects and enhancing the nonlinearities. We also show that when the coupling light involves a standing-wave pattern, the periodic modulation of linear and nonlinear spectra results in an efficient scheme for the electromagnetically induced grating (EIG). In particular, the diffraction efficiency is influenced by changing the distance between the quantum system and plasmonic nanostructure. The proposed scheme may find potential applications in future nanoscale photonic devices.

Spatially Structured Optical Effects in a Four‐Level Quantum System Near a Plasmonic Nanostructure

“…We further assume that the upper V‐type subsystem involving , and lies within the surface‐plasmon bands of the plasmonic nanostructure, while the lower V‐type subsystem containing , and is spectrally away from the surface‐plasmon bands, hence it is not influenced by the plasmonic nanostructure. [ 30,31,36,38,40,41,46–48,50,56,63 ] This leads the spontaneous decay in lower V subsystem due to the interaction of the quantum system with the free‐space vacuum electromagnetic modes. The quantum configuration considered here can be realized in hyperfine sublevels of D lines in alkali‐metal atomic systems, such as 85 Rb and 87 Rb, [ 31,32,40 ] as well as in quantum dots, like in dual CdSe/ZnS/CdSe quantum dots.…”

“…The coherent interaction of light with the quantum systems near plasmonic nanostructures may lead to several quantum coherence and interference phenomena with updated properties compared to the isolated quantum systems. Some of these effects are optical transparency and slow light, [ 30–32 ] gain without inversion, [ 33–36 ] control of spontaneous emission, [ 37–41 ] Fano effects in energy absorption, [ 42–44 ] controlled quantum entanglement, [ 45,46 ] electromagnetically induced grating, [ 47–50 ] existence and manipulation of optical bistability, [ 51,52 ] enhanced second‐harmonic generation, [ 53 ] modified four‐wave mixing, [ 54,55 ] and enhanced Kerr nonlinearity. [ 56–63 ]…”

“…The double‐V‐type quantum system displays effects of quantum interference in spontaneous emission when placed near the periodic plasmonic nanostructure [ 38 ] and its optical properties have been analyzed in various studies exhibiting very interesting effects. [ 30,31,36,41,46–48,50,56,63 ] In this work, we study the angular dependence of optical susceptibility of the quantum system. We show that the azimuthally varying linear and nonlinear patterns can be controlled though different external parameters such as the distance of the quantum system from the surface of plasmonic nanostructure and the vorticity of twisted probe beam.…”

Controllable Atom-Photon Entanglement Via Quantum Interference Near Plasmonic Nanostructure

“…Quenching or enhancement of the spontaneous emission [28][29][30] , gain without population inversion 31 , enhancement of nonlinear optical response [32][33][34] are described in hybrid plasmonic nanostructure. The effect of plasmonic nanostructure on optical grating 35 , probe field absorption 36 , and slow-light propagation 37 was also proposed. Now, we study the entanglement of a five-level quantum emitter coupled to a plasmonic nanostructure, namely a periodic 2D array of metal-coated dielectric nanospheres, and its spontaneous emission field.…”

Controllable atom-photon entanglement via quantum interference near plasmonic nanostructure

“…Quenching or enhancement of the spontaneous emission [28][29][30] , gain without population inversion 31 , enhancement of nonlinear optical response [32][33][34] are described in hybrid plasmonic nanostructure. The effect of plasmonic nanostructure on optical grating 35 , probe field absorption 36 , and slow-light propagation 37 was also proposed. www.nature.com/scientificreports/ Now, we study the entanglement of a five-level quantum emitter coupled to a plasmonic nanostructure, namely a periodic 2D array of metal-coated dielectric nanospheres, and its spontaneous emission field.…”