Mechanisms of Thickness-Dependent Nonlinear Optical Processes and Ultrafast Dynamics in NbOCl2
发布时间：2025-09-15
点击次数：
DOI码：10.1021/acs.jpclett.5c01968
发表刊物：The Journal of Physical Chemistry Letters
摘要：NbOCl2 has garnered interest owing to its second-order nonlinear optical properties, but the influence of thickness on its third-harmonic generation (THG) and excited-state dynamics has not been fully investigated. Here, mechanically exfoliated NbOCl2 flakes were found to produce THG and second-harmonic generation (SHG), simultaneously, and to show a nonmonotonic dependence on sample thickness. The increase in thickness leads to a decrease in the bandgap. The transient absorption spectrum of NbOCl2 reveals an enhancement of the long-lived excited-state absorption (ESA) at 2.62 eV and a red-shift of the band-edge absorption (BEA). The ground-state bleaching (GSB) exhibits an accelerated relaxation. Additionally, THG of NbOCl2 arising from three-photon resonant absorption is competing with SHG, while their optimal excitation band varies with thickness. This study improves our understanding of the mechanisms of the thickness of NbOCl2 and the development of ultrafast photonics and all-optical switching.
合写作者：Jun He, Yingwei Wang, Jun Li, Haixia Zhu, Zhaozhe Chen
第一作者：Jie Zhang
论文类型：期刊论文
通讯作者：Si Xiao#, Zhihui Chen#
学科门类：理学
一级学科：物理学
文献类型：J
卷号：16
期号：36
页面范围：9529-9536
是否译文：否
发表时间：2025-09-15
收录刊物：SCI