Exciton-driven giant non-linear overtone signals from buckled hexagonal monolayer GaAs

Himani Mishra, Sitangshu Bhattacharya

We report here a giant $\left|{\chi }_{baa}^2\right|=$780 pm/V second harmonic and $\left|{\chi }_{aaaa}^3\right|=$1.4$\times$10${}^{-17}$ m${}^2$/V${}^2$ third harmonic signal from single a…