Nonlinear coherent light-matter interaction in 2D MoSe$_2$ nanoflakes for all-optical switching and logic applications

TL;DR

This paper demonstrates the strong nonlinear optical response of 2D MoSe$_2$ nanoflakes, enabling all-optical switching, logic, and diode applications through spatial self-phase and cross-phase modulation effects.

Contribution

It introduces a novel nonlinear optical characterization of MoSe$_2$ nanoflakes and designs all-optical devices leveraging their nonlinear properties for photonic applications.

Findings

Measured nonlinear refractive index and susceptibility of MoSe$_2$ NFs.

Demonstrated all-optical diode using MoSe$_2$/SnS$_2$ hybrid structure.

Implemented all-optical logic gates and information conversion.

Abstract

We report a strong nonlinear optical response of 2D MoSe$_2$ nanoflakes (NFs) through spatial self-phase modulation (SSPM) and cross-phase modulation (XPM) induced by nonlocal coherent light-matter interactions. The coherent interaction of light and MoSe$_2$ NFs creates the SSPM of laser beams, forming concentric diffraction rings. The nonlinear refractive index ($n_2$) and the third-order broadband nonlinear optical susceptibility ($\chi^{(3)}$) of MoSe$_2$ NFs are determined from the self diffraction pattern at different exciting wavelengths of 405, 532, and 671 nm with varying the laser intensity. The evolution and deformation of diffraction ring patterns are observed and analyzed by the `wind-chime' model and thermal effect. By taking advantage of the reverse saturated absorption of 2D SnS$_2$ NFs compared to MoSe$_2$, an all-optical diode has been designed with MoSe$_2$/SnS$_2$ hybrid structure to demonstrate the nonreciprocal light propagation. Also a few other optical devices based on MoSe$_2$ and other semiconducting materials such as Bi$_2$Se$_3$, CuPc, and graphene have been investigated. The all-optical logic gates and all-optical information conversion have been demonstrated through the XPM technique using two laser beams. The proposed optical scheme based on MoSe$_2$ NFs has been demonstrated as a potential candidate for all-optical nonlinear photonic devices such as all-optical diodes and all-optical switches.