Qualified type:	Scientific journal article
Title:	Crystalline phase effects on the nonlinear optical response of MoS2 and WS2 nanosheets: Implications for photonic and optoelectronic applications
Creator:	[EL] Ταγματάρχης, Νίκος[EN] Tagmatarchis, Nikos Stavrou, Michalis Chazapis, Nikolaos Nikoli, Eleni Arenal, Raul Couris, Stelios
Publisher:	American Chemical Society
Date:	2022
Language:	English
DOI:	10.1021/acsanm.2c03709
Abstract:	In the present work, some MoS2 and WS2 nanosheets were prepared and characterized. Depending on the preparation procedures, trigonal prismatic (2H) or octahedral (1T) coordination of the metal atoms was obtained, exhibiting metallic (1T) or semiconducting (2H) character. Both MoS2 and WS2 nanosheets were found exhibiting large nonlinear optical (NLO) responses, strongly dependent on their metallic (1T) or semiconducting (2H) character. Therefore, the semiconducting character of MoS2 and WS2 exhibits positive nonlinear absorption and strong self-focusing behavior, while their metallic character counterparts exhibit strong negative nonlinear absorption and important self-defocusing behavior. In addition, the semiconducting MoS2 and WS2 were found exhibiting important and very broadband optical limiting (OL) action extending from 450 to 1750 nm. Therefore, by selecting the crystalline phase of the nanosheets, that is, their semiconduction/metallic character, their NLO response can be greatly modulated. The results of the present work demonstrate unambiguously that the control of the crystalline phase of MoS2 and WS2 provides an efficient strategy for 2D nanostructures with custom-made NLO properties for specific optoelectronic and photonic applications such as OL, saturable absorption, and optical switching.
Reference title:	ACS Applied Nano Materials
Volume/Chapter:	5
Pages:	16674–16686
Subject:	[EL] Φυσική και θεωρητική χημεία[EN] Physical and theoretical chemistry [EL] Νανοτεχνολογία[EN] Nanotechnology [EL] Φασματοσκοπία[EN] Spectroscopy
Keywords:	Molybdenum disulfide Tungsten disulfide Optical limiting Nonlinear optical properties Z-scan technique
Rights holder:	2022 American Chemical Society
Publisher link:	https://pubs.acs.org/doi/10.1021/acsanm.2c03709?ref=pdf
Appears in Collections:	Ινστιτούτο Θεωρητικής και Φυσικής Χημείας (ΙΘΦΧ) - Επιστημονικό έργο