2025/07/20 by Dipanwita Mitra, Guilherme S. L. Fabris, Mitra, Dipanwita +17
Engineering · Materials Science · Physics and Astronomy · #2D Materials and Applications #Advanced Fiber Laser Technologies #FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci) #Nonlinear Optical Materials Studies #Optics (physics.optics)
paper · pdf · doi:10.48550/arxiv.2507.14786
openalex publication_date 2025/07/20 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Light-matter interactions in two-dimensional (2D) materials have gained significant interest due to their distinctive optical and electronic properties. Recently, silicates have emerged as a promising new class of 2D materials, but their nonlinear optical properties remain largely unexplored. In this study, we demonstrate layer-dependent nonlinear absorption and optical limiting capabilities of 2D muscovite using femtosecond laser excitation at 450 nm. The two-photon absorption (TPA) coefficient is highly sensitive to both the number of layers and excitation intensity, increasing markedly from (3.91+/-0.06)x103 cm GW-1 in multilayer structures to (6.94+/-0.17)x105 cm GW-1 in the monolayer limit at a peak intensity of 68 GW cm-2, highlighting a strong layer-dependent enhancement in nonlinear absorption. Additionally, monolayer muscovite exhibits an optical limiting threshold of 1.46 mJ cm-2, outperforming graphene and other 2D dichalcogenides. This enhanced TPA arises from quantum confinement and intrinsic lattice defects that facilitate nonlinear optical transitions. Density functional theory reveals that liquid-phase exfoliation disrupts potassium interlayers and induces oxygen vacancies, generating mid-gap electronic states that significantly enhance TPA. These insights open new avenues for designing low-fluence, high-efficiency optical limiters using 2D silicates.