Plasmon-induced phase grating via nonlinear modulation

Seyyed Hossein Asadpour, Ali Panahpour, Mahmoud Jafari

Zhuan-Zhuan Liu, Yu-Yuan Chen, Jia-Yu Yuan +1 more

Ji-Bing Liu, Na Liu, Tang-Kun Liu +4 more

Bin Xie, Xin Cai, Zhihong Xiao

Azar Vafafard, Mostafa Sahrai, Vahid Siahpoush +2 more

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.

Mehdi Javanmard

Abstract We theoretically study a two-dimensional electromagnetically induced phase grating in a four-level quantum system located near plasmonic metamaterials consisting of a periodic two-dimensional array of metal-coated dielectric nanospheres. The four-level quantum system interacts with a weak-probe laser field and a strong coherent coupling field with a standing-wave pattern. In the presence of plasmonic metamaterials the quantum system becomes sensitive to the relative phase between applied light. Therefore, the linear absorption and Kerr nonlinearity of the medium become phase dependent. Here, due to the standing-wave pattern of coupling light, an absorptive grating or phase grating can be formed in the quantum system. In our proposed model, we show that the diffraction efficiencies of the grating are related to the relative phase between applied fields, when the quantum system is located at different distances from plasmonic metamaterials.