Size-Dependent Nonlinear Optical Response of Black\nPhosphorus Liquid Phase Exfoliated Nanosheets in Nanosecond Regime

Abstract

Atomically\nthin materials are exhibiting unique physical properties. This work\ninvestigates the size dependent nonlinear optical response of black\nphosphorus nanosheets for nanosecond laser pulses. Material is prepared\nwith the use of Liquid Phase Exfoliation. Experiments are performed\nusing open aperture <i>Z</i>-scan technique at 532 nm wavelength\nwith ND:Yag, 10 Hz ns as laser source. We report that the nonlinear\nabsorption coefficient of black phosphorus is strongly dependent on\nflake lateral dimension as well as laser intensity.