Exceptionally High Nonlinear Optical Response in Two-dimensional Type II Dirac Semimetal Nickel Di-Telluride (NiTe₂)

Author(s)

Goswami, Saswata ; de Oliveira, Caique Campos ; Ipaves, Bruno ; Mahapatra, Preeti Lata ; Pal, Varinder ; Sarkar, Suman ; Autreto, Pedro A. S. ; Ray, Samit K. ; Tiwary, Chandra Sekhar

• Document type: Journal article
• Source: LASER & PHOTONICS REVIEWS; v. N/A, p. 16-pg., 2025-03-10.

Abstract

Nickel ditelluride (NiTe2) is a newly identified Type-II Dirac semimetal, showing novel characteristics in electronic transport and optical experiments. This study explores the nonlinear optical properties of 2D NiTe2 using experimental and computational techniques (density functional theory-based approach). Few layered 2D-NiTe2 are synthesized using liquid phase exfoliation (LPE), which is characterized using X-ray diffraction technique, transmission electron, and atomic force microscopy. The nonlinear refractive index (n(2)) and third-order nonlinear susceptibility (chi((3))(total)) of the prepared 2D-NiTe2 are determined from the self-induced diffraction pattern generated using different wavelengths (lambda = 650, 532, and 405 nm) in the far field. In addition, the diffraction pattern generated by spatial self-phase modulation (SSPM) is further verified by varying concentration (2D-NiTe2 in the IPA solvent), wavelength (of incoming laser beams), and cuvette width (active path length). The high value of third-order nonlinear susceptibility for a monolayer chi((3))(monolayer) (in order of x10(-9) e.s.u.) determined using SSPM in the 2D-NiTe2 can be attributed to the laser-induced hole coherence effect. Last, utilizing the reverse saturable absorption property of 2D-hBN, asymmetric light propagation is also demonstrated in the 2D-NiTe2/2D-hBN heterostructure. (AU)

• FAPESP's process: 24/11376-6 - pH-Universal Catalysts Based on 2D Nanostructures and van der Waals Heterostructures for Hydrogen Evolution Reactions
• Grantee: Caique Campos de Oliveira
• Support Opportunities: Scholarships in Brazil - Doctorate