Related Experiment Video
Updated: Jan 8, 2026
09:46
Fabrication and Characterization of High-Q Silicon Nitride Membrane Resonators
Published on: August 8, 2025
1.0K
Unconventional high-harmonic generation in resonant membrane metasurfaces
Pavel Tonkaev1, Felix Richter2, Ivan Toftul1
1Nonlinear Physics Center, Research School of Physics, Australian National University, Canberra, ACT, Australia.
Nature Communications
|December 22, 2025
Summary
Highly resonant metasurfaces driven by quasi-bound states in the continuum exhibit unconventional nonlinearities in high-harmonic generation (HHG). These systems display non-integer intensity dependencies, challenging established scaling laws for HHG in solids.
Area of Science:
- Optics and Photonics
- Condensed Matter Physics
- Quantum Electronics
Background:
- High-harmonic generation (HHG) in solids is crucial for attosecond sources and ultrafast electron dynamics.
- Metasurfaces enhance HHG efficiency via local field enhancement and phase matching relaxation.
- Existing theories assume HHG follows integer-power scaling laws, similar to bulk materials.
Purpose of the Study:
- To investigate high-harmonic generation in highly resonant metasurfaces.
- To explore the influence of quasi-bound states in the continuum on HHG scaling laws.
- To uncover novel nonlinear optical phenomena in metasurface-enhanced HHG.
Main Methods:
- Experimental realization of highly resonant metasurfaces.
- Theoretical modeling of light-matter interaction in metasurfaces.
- Analysis of harmonic power scaling with driving laser intensity.
- Investigation of higher-order nonlinear susceptibility contributions.
Main Results:
- Demonstration of non-integer intensity dependencies in metasurface-enhanced HHG.
- Observation of unconventional nonlinearities breaking standard scaling laws.
- Attribution of these effects to strong local fields from high-Q resonances.
- Significant alteration of higher-order susceptibility contributions.
Conclusions:
- Highly resonant metasurfaces driven by quasi-bound states in the continuum exhibit unique nonlinear optical properties.
- These findings challenge conventional understanding of HHG scaling in solids.
- The study opens new avenues for controlling light-matter interactions at the nanoscale.
Related Concept Videos
01:14Sound Waves: Resonance
3.2K
Resonance is produced depending on the boundary conditions imposed on a wave. Resonance can be produced in a string under tension with symmetrical boundary conditions (i.e., has a node at each end). A node is defined as a fixed point where the string does not move. The symmetrical boundary conditions result in some frequencies resonating and producing standing waves, while other frequencies interfere destructively. Sound waves can resonate in a hollow tube, and the frequencies of the sound...
3.2K
01:28Standing Waves in a Cavity
1.4K
A household microwave and lasers are examples of standing electromagnetic waves in a cavity. When two conducting metal plates are placed parallel at the nodal planes, it creates a cavity where standing waves are formed. The cavity between the two planes is analogous to a stretched string held at the points x = 0 and x = L. Here, the distance 'L' between the two planes must be an integer multiple of half of the wavelength. The wavelengths that satisfy this condition are given by:
1.4K
01:12Double Resonance Techniques: Overview
662
Double resonance techniques in Nuclear Magnetic Resonance (NMR) spectroscopy involve the simultaneous application of two different frequencies or radiofrequency pulses to manipulate and observe two distinct nuclear spins. One important application of double resonance is spin decoupling, which selectively suppresses coupling with one type of nucleus while observing the NMR signal from another nucleus, simplifying the spectrum and enhancing resolution.
Spin decoupling is usually achieved by...
Spin decoupling is usually achieved by...
662
02:16Resonance and Hybrid Structures
24.6K
According to the theory of resonance, if two or more Lewis structures with the same arrangement of atoms can be written for a molecule, ion, or radical, the actual distribution of electrons is an average of that shown by the various Lewis structures.
Resonance Structures and Resonance Hybrids
The Lewis structure of a nitrite anion (NO2−) may actually be drawn in two different ways, distinguished by the locations of the N–O and N=O bonds.
Resonance Structures and Resonance Hybrids
The Lewis structure of a nitrite anion (NO2−) may actually be drawn in two different ways, distinguished by the locations of the N–O and N=O bonds.
24.6K