AUTHOR=Mirershadi Soghra , Sattari Farhad , Alipour Afshin , Mortazavi Seyedeh Zahra TITLE=Non-linear Thermo-Optical Properties of MoS2 Nanoflakes by Means of the Z-Scan Technique JOURNAL=Frontiers in Physics VOLUME=8 YEAR=2020 URL=https://www.frontiersin.org/journals/physics/articles/10.3389/fphy.2020.00096 DOI=10.3389/fphy.2020.00096 ISSN=2296-424X ABSTRACT=

The non-linear thermo-optical response of MoS2 nanoflakes was investigated using the Z-scan technique, employing TM00-mode with a CW-laser diode operating at a wavelength of 532 nm. The systems were found to display a strong non-linear response, dominated by non-linear refraction. The effect of the thickness of the MoS2 layer, deposited on a glass substrate, on the non-linear susceptibility was studied. Furthermore, in this study, the effects of modifying the thickness of the MoS2 nanoflakes on the non-linear optical phenomena, such as self-focusing and self-defocusing was investigated for the first time. In all cases, the non-linear absorption and refraction were determined. The corresponding third-order susceptibilities and second-order hyperpolarizability were calculated to be as large as 10–7 (esu) and 10–32 (esu), under laser excitation, respectively. Showing large third-order optical non-linearity suggests the potential of the MoS2 nanoflakes in photonics applications.