Strain Control of Third Harmonic Generation in Nb2SiTe4 Driven by Tuneable Anisotropic Characteristics

Release time:2024-12-18

DOI number:10.1002/adfm.202422428

Journal:Advanced Functional Materials

Key Words:third harmonic generation, nonlinear optics, anisotropic two-dimensional materials, strain engineering

Abstract:Strain engineering constitutes one of the main control knobs for material properties. The material’s crystal and band structure can be strongly modified by mechanical strain, thus tailoring the electronic and photonic properties towards specific applications. However, the strain control of the higher-order nonlinear optical (NLO) processes in crystals characterized by in-plane anisotropy remains mostly unexplored. Here, we demonstrated that two-dimensional ternary Nb2SiTe4 crystals provide an excellent platform for tuning NLO properties with uniaxial strain due to the inherently anisotropic band structure around the fundamental band gap in the near-infrared region. By realizing resonant conditions between the interband excitations and third harmonic signals, we observed a record high third-order susceptibility of 2.43×10^(-18) m^2⁄V^2 , exceeding by over an order of magnitude the values reported for commonly used NLO crystals. The measurements of the third harmonic intensity as a function of the linear polarization revealed that the anisotropic characteristics of Nb2SiTe4 can be tuned into qualitatively different regimes by the application of a uniaxial strain along the principal crystallographic axes. Notably, with increasing strain, the characteristic anisotropic direction can be reoriented. Our findings provide unique perspectives for applying the modulation of the broadband NLO properties enabled by anisotropic materials in optoelectronics and all-optical devices.

Co-author:Zhenzhen Wan, Wenzhe Zhou, Tao Xu, Kostya S. Novoselov

First Author:Yihang Ouyang#, Jin Dai#

Indexed by:Journal paper

Correspondence Author:Maciej Koperski*, Zhihui Chen*, Jun He*

Discipline:Natural Science

Document Type:J

Volume:2422428

Translation or Not:no

Date of Publication:2024-12-26

Included Journals:SCI

Links to published journals:https://onlinelibrary.wiley.com/doi/10.1002/adfm.202422428