Search arXivSearch

arXiv · 2604.18501

Continuous Wave Second Harmonic Generation from an Etchless Lithium Niobate Resonant Metasurface

Abstract

Nonlinear metasurfaces provide a route to compact frequency conversion by replacing phase matching and long interaction lengths with resonantly enhanced light matter interaction in subwavelength structures. Extending this capability to continuous wave (CW) operation is particularly important for applications requiring narrow linewidth, stable frequency, and stationary optical fields, but remains extremely challenging. Here, we demonstrate CW second-harmonic generation on a transmission mode, etchless thin film lithium niobate platform enabled by a patterned silicon rich nitride metasurface. This hybrid design combines guided mode resonance coupling, low optical loss, and CMOS compatible processing while keeping most of the optical mode confined in the unpatterned lithium niobate, yielding a measured quality factor of ~2300. Clearly resolved SHG is achieved under sub-kW/cm^2 CW pumping, with a normalized conversion efficiency of 0.156 % cm^2/GW in the low power regime. Interestingly, our work reveals that CW resonant SHG in metasurfaces can exhibit pronounced transient dynamics, including power dependent resonance evolution, overshoot, and nonideal scaling. These findings establish etchless LN SRN metasurfaces as a promising platform for compact CW nonlinear photonics, and show that resonance dynamics are central to the operation and evaluation of CW driven nonlinear metasurfaces.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Zetian Chen, Noa Mazurski, Uriel Levy. 2026-04-20. Continuous Wave Second Harmonic Generation from an Etchless Lithium Niobate Resonant Metasurface. https://arxiv.org/abs/2604.18501

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

High-Resolution Sensing via Quantum States Discrimination

High-resolution sensing plays a significant role in scientific research and industrial production, but the practical implementation is constrained by the physical mechanisms of the sensors. To address the critical limitation, we propose a high-resolution sensing approach based on quantum state discrimination. Distinct from conventional strategies, the proposed approach constructs measurement operators in the orthogonal complement space rather than eigenspace of the eigenstate, thereby notably improving the discriminability among quantum states. Moreover, the experimental results via an optical microcavity demonstrate a potential sensing resolution of 4 $\times$ 10\textsuperscript{-6} \degree C and 18 p$ε$ respectively for temperature and strain, and further verify the feasibility of simultaneous sensing of the two parameters. This work establishs a universal approach for high-resolution sensing, and may be extended to different sensing platforms across various application scenarios.

physics.optics

9.8-GW tabletop attosecond light source

The generation of attosecond pulses has enabled real-time observation and manipulation of coherent electron dynamics, yet their low peak power has hindered the development of advanced attosecond pump-probe spectroscopy and attosecond nonlinear metrology. Here we overcome this limitation by generating a 2.8 uJ, 292 as isolated attosecond pulses with a peak power of 9.8GW,the highest pulse energy and peak power reported for a tabletop isolated attosecond source.This is achieved by combining a 2.4TW, few-cycle(8.3 fs) two-color synthesizer with a loose focusing geometry that enables macroscopic phase-matching. The synthesizer features a stabilized carrier-envelope phase and an actively synchronized relative time delay between the two-color channels, ensuring high stability and reproducibility. This high-power tabletop attosecond source will open up nonlinear effect experiments that were previously inaccessible with lower-power IAPs, establishing a foundation for advanced attosecond spectroscopy and nonlinear metrology.

physics.optics

Square-Root Higher-Order Exceptional Points with Symmetry-Induced Multiple Spectral Responses

We generalize square-root procedure to non-Hermitian systems with finite lattices, providing a spectral operation scheme applicable to arbitrary tight-binding models. Via this generalized square-root approach, we construct novel chiral-symmetric higher-order exceptional points (EPs) with multiple spectral responses. By taking square-root of a parent Hamiltonian hosting an $n$th-order EP (EP$_n$), an EP$_{2n+1}$ chiral-symmetric square-root system is obtained, whose lattice sites are inherited from both the parent system and an auxiliary residual system. The chiral-symmetry-induced structure of the generalized eigenspace enables onsite and coupling perturbations to selectively generate spectral responses of different orders. The proposed scheme is universal, applicable to any existing tight-binding EP system and iterable to generate EPs of arbitrarily high order. With enriched ultrasensitive spectral responses, the chiral-symmetric higher-order EP system provides a promising platform for signal amplification, detection and non-Hermitian control.

physics.optics