Search arXiv⌕ Search

arXiv · 1812.09465

Lattice effect on electric and magnetic resonance overlap in periodic array

Abstract

Designing the shape of silicon nanoparticles has been shown to be an effective approach to increasing overlap between electric and magnetic dipole resonances thereby achieving directional scattering and decrease of reflection. Variations of disk diameter and/or height affect resonances differently and can thus result in resonance overlap. In most of the studies, the disks are arranged in a periodic array where the periodicity is varied together with disk diameter, but the role of lattice effect is neglected. Here we theoretically study a periodic array of disks and show that the contribution of the lattice effect in shifting resonance positions is comparable to the effect of the diameter change. We demonstrate that the lattice effect is important even when the wavelength of diffraction remains on the blue side from electric and magnetic dipole resonances and there are no additional lattice resonances are excited. Period and disk dimensions are chosen so that the resonances overlap in the proximity of the telecommunication wavelength which is of great practical interest.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Viktoriia E. Babicheva, Jerome V. Moloney. 2018-12-22. Lattice effect on electric and magnetic resonance overlap in periodic array. https://doi.org/10.1515/nanoph-2018-0107

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

KEEP EXPLORING

Related papers

Plasmonic Metasurfaces for Magnetic Skyrmion Control via the Inverse Faraday Effect

Magnetic skyrmions hold high promise for low power spintronic and neuromorphic computing. However, existing manipulation schemes rely predominantly on local thermal excitation, rendering nucleation stochastic and lacking a non-destructive mechanism for targeted erasure. Here, we demonstrate a deterministic, optomagnetic field-driven paradigm for fast, all-optical writing and erasing of magnetic skyrmion crystals using a magneto-plasmonic metasurface. By tailoring surface lattice resonances in a periodic nanodisk array, circularly polarized light excites giant super-circular optical spin densities that drive intense circulating drift photocurrents via the inverse Faraday effect. This delivers synchronized picosecond magnetic field pulses into an adjacent magnetic multilayer. Micromagnetic simulations reveal that a single optical pulse deterministically nucleates stable Néel skyrmions through a transient Bloch to Néel relaxation pathway governed by optical helicity and interfacial Dzyaloshinskii Moriya interaction. Crucially, reversing incident light helicity allows on-demand topological reconfiguration: under a confining bias field, the inverted optomagnetic field unwinds pre existing skyrmions to restore a uniform ground state. Furthermore, we demonstrate the targeted writing of stable skyrmionium states. By bypassing stochastic thermal cycles and achieving reversible topological control on picosecond timescales, this work bridges nanophotonics, plasmonics, and magnetism, establishing a scalable foundation for high-speed, reconfigurable information processing and unconventional computing.

physics.optics↗

Closing the Loop in Epitaxy with Machine Learning: Joint Optimization of Growth and Geometry in On-Chip Lasers

Achieving device-to-device reproducibility is a critical bottleneck for scalable photonic integrated circuits, as subtle variations in bottom-up epitaxial growth and fabrication severely limit yield. We present a machine learning workflow for III-V multi-quantum well microring lasers that first optimizes growth and geometry parameters via multi-objective Bayesian optimization, then leverages variational autoencoders (VAEs) to attribute residual device-to-device variability to its underlying sources. By explicitly targeting threshold variance alongside absolute performance, we demonstrate 100% lasing yield across all designs. The optimized multi-quantum well microring laser fields achieved a median lasing threshold of $16~μ\mathrm{J}\,\mathrm{cm}^{-2}\,\mathrm{pulse}^{-1}$, a $73\%$ reduction in threshold variance relative to the previously reported best values, and a median emission wavelength of $1333~\mathrm{nm}$, in the telecommunications O-band. Furthermore, to diagnose residual performance dispersion under nominally identical conditions, VAEs were used to isolate the key components of device morphology that impact performance. This analysis successfully decoupled geometric from material disorder, quantitatively linking previously unmeasured morphological variations to population-level threshold fluctuations. This data-driven workflow bridges the gap between fundamental epitaxy and reliable manufacturing, establishing a generalizable blueprint for designing and yield-optimizing complex, non-linear optoelectronic devices.

physics.optics↗

Frequency Attraction and Repulsion in Lasers with Complex Mutual Coupling

We experimentally investigate laser synchronization under complex mutual coupling, featuring both dissipative and dispersive components. Using a reconfigurable digital degenerate cavity laser with precise control over system parameters, we show that complex coupling can induce both frequency attraction and repulsion, in contrast to common models of coupled oscillators. Furthermore, we show that these frequency shifts can be exploited to significantly enhance global synchronization in multi-laser arrays. Comparison with numerical and theoretical results indicate that amplitude dynamics of complex coupled lasers play an important role in the observed phenomena. Our results establish a versatile platform for exploring non-Hermitian physics and topological states in tailored laser networks.

physics.optics↗