Author(s): Ke, YX (Ke, Yuxuan); Li, C (Li, Chun); Liang, Y (Liang, Yin); Zhang, X (Zhang, Xi); Song, JP (Song, Jiepeng); Li, RJ (Li, Ruijie); Liu, L (Liu, Lei); Dai, JF (Dai, Junfeng); Wei, ZM (Wei, Zhongming); Zhang, Q (Zhang, Qing)
 
Source: NANOSCALE DOI: 10.1039/d3nr00526g  Early Access Date: MAY 2023  
 
Abstract: Two-dimensional (2D) van der Waals layered gamma-type indium selenide (gamma-InSe) holds great promise for the development of ultrathin and low-energy-consumption nonlinear optical devices due to its broken inversion symmetry regardless of layer number. Nevertheless, the 2D InSe thin flakes still exhibit short light-matter interaction lengths, thus resulting in low efficiencies of nonlinear optical processes. In this work, we provide a facile 2D semiconductor-metal structure consisting of InSe thin flakes (thickness: 11-54 nm) on planar Au film, which exhibits great second-harmonic generation (SHG) enhancement by a factor of up to 1182. The SHG enhancement is attributed to the interference effect-induced strong electric field in highly absorbing InSe; meanwhile, the increase in reflectivity by Au film also plays an important role. Furthermore, the InSe thickness and excitation wavelength dependences of enhancement factors are revealed. This work provides a convenient approach to developing high-efficiency 2D nonlinear optical devices with ultrathin form.
 
Accession Number: WOS:000998491700001
 
PubMed ID: 37260188
 
Author Identifiers:
 
Author Web of Science ResearcherID ORCID Number
 
Zhang, Qing  N-6703-2014 0000-0002-6869-0381
 
wei, zhong ming          0000-0002-6237-0993
 
Li, Ruijie  0000-0001-9001-8201
 
Liu, Lei          0000-0002-7226-8423
 
ISSN: 2040-3364
 
eISSN: 2040-3372