Enhancement of Raman scattering in dielectric nanostructures with electric and magnetic Mie resonances

Frizyuk, Kristina; Hasan, Mehedi; Krasnok, Alex; Alù, Andrea; Petrov, Mihail

doi:10.1103/physrevb.97.085414

Cited by 46 publications

(37 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The model also revealed that the crystallization dynamics can give rise to secondary antennas embedded into the primary nanostructures, which broadens the horizons of light harvesting and thermal management at the nanoscale. This approach can be extended to many different materials and thermally-activated processes, including laser resonant printing (28), diffusion-based doping of semiconductors, nanofabrication of all-dielectric and hybrid devices for enhanced vibrational spectroscopy (29)(30)(31) and photothermal therapy.…”

Section: Discussionmentioning

confidence: 99%

Using optical resonances to control heat generation and propagation in silicon nanostructures

Danesi

Alessandri

2019

Phys. Chem. Chem. Phys.

View full text Add to dashboard Cite

Here we propose a new computational approach to light-matter interactions in silicon nanopillars, which simulates heat generation and propagation dynamics occurring in continuous wave laser processing over a wide temporal range (from 1 fs to about 25 hours). We demonstrate that a rational design of the nanostructure aspect ratio, type of substrate, laser irradiation time and wavelength enables amorphous-to-crystalline transformations to take place with a precise, sub-wavelength spatial localization. In particular, we show that visible light can be exploited to selectively crystallize internal region of the pillars, which is not possible by conventional treatments. A detailed study on lattice crystallization and reconstruction dynamics reveals that local heating drives the formation of secondary antennas embedded into the pillars, highlighting the importance of taking into account the spatial and temporal evolution of the optical properties of the material under irradiation. This approach can be easily extended to many types of nanostructured materials and interfaces, offering a unique computational tool for many applications involving opto-thermal processes (fabrication, data storage, sensing, catalysis, resonant laser printing, opto-thermal therapy etc…).

show abstract

Section: Discussionmentioning

confidence: 99%

Using optical resonances to control heat generation and propagation in silicon nanostructures

Danesi

Alessandri

2019

Phys. Chem. Chem. Phys.

View full text Add to dashboard Cite

show abstract

“…Here, we show how far-field Raman spectroscopy -a technique primarily known for sensing [5] -can be used as a versatile characterization tool for high-refractive-index nanostructures. Raman spectroscopy measures inelastic scattering of photons from phonon and vibrational modes in materials and its signal strength depends dramatically on the electric near-field enhancement [6,7,8]. This dependency has driven research in surface-enhanced Raman spectroscopy to create surfaces that amplify the local electric field outside nanostructures for sensing of nearby molecules [9].…”

Section: Introductionmentioning

confidence: 99%

“…The intensity of Raman scattering is amplified by the internal near-field enhancement produced by Mie resonances in silicon nanoparticles [7,8,22]. This has been exploited for detecting these resonances, but also for other applications such as thermometry, crystallinity characterization and nonlinear spectroscopy [23,24,25,26,27].…”

Section: Introductionmentioning

confidence: 99%

“…By comparing the Raman signal on and off resonance, we are able to map out the optical resonances and the internal near-field enhancement. Inspired by the recent theoretical description of Raman scattering [7,8], we explain our experimental observations using a model based on the enhancement of the stored electric energy in the nanostructures. Our theoretical model is in excellent agreement with our measurements.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Probing optical resonances of silicon nanostructures using tunable-excitation Raman spectroscopy

et al. 2019

View full text Add to dashboard Cite

Optical materials with a high refractive index enable effective manipulation of light at the nanoscale through strong light confinement. However, the optical near field, which is mainly confined inside such high-index nanostructures, is difficult to probe with existing measurement techniques. Here, we exploit the connection between Raman scattering and the stored electric energy to detect resonance-induced near-field enhancements in silicon nanostructures. We introduce a Raman setup with a wavelength-tunable laser, which allows us to tune the Raman excitation wavelength and thereby identify Fabry-Pérot and Mie type resonances in silicon thin films and nanodisk arrays, respectively. We measure the optical near-field enhancement by comparing the Raman response on and off resonance. Our results show that tunableexcitation Raman spectroscopy can be used as a complimentary far-field technique to reflection measurements for nanoscale characterization and quality control. As proof-of-principle for the latter, we demonstrate that Raman spectroscopy captures fabrication imperfections in the silicon nanodisk arrays, enabling an all-optical quality control of metasurfaces.

show abstract

“…It has been shown through numerical simulations and also experimental validation that dimer structures made of high refractive index materials produce both electric and magnetic hotspots in infrared 11 and in the visible spectral range 8,12 . The enhancement is produced by the displacement currents and the electric and magnetic dipole-dipole interactions in the dielectric dimers 11,13 . Dielectric dimers not only enhance the field, but they also provide control over the directivity of the far field radiation of the emitters, without quenching the nearby emitters and lowering their quantum efficiency 8 .…”

Section: Introductionmentioning

confidence: 99%

Lattice Resonances and Local Field Enhancement in Array of Dielectric Dimers for Surface Enhanced Raman Spectroscopy

Černigoj

Silvestri

Stoevelaar

et al. 2018

Sci Rep

View full text Add to dashboard Cite

In this paper, we propose the use of high refractive index dimers for the realization of a surface enhanced Raman spectroscopy substrate, with an average enhancement factor comparable to plasmonic structures. The use of low loss dielectric materials is favorable to metallic ones, because of their lower light absorption and consequently a much lower heating effect of the substrate. We combined two different mechanisms of field enhancement to overcome the main weakness of dielectric dimers: a low enhancement factor compared to the plasmonic ones. A first mechanisms is associated to surface lattice resonances. This generates a narrow-band high enhancement, which is exploited to enhance the excitation light. A second mechanism exploits the local field enhancement between the dimers’ resonators, for the band where the molecule Raman emission spectrum is located. The fact that both field enhancements can be tuned by acting on separate geometric parameters, makes possible to optimize the design for many different molecules. The optimized structure and its performance is presented together with a discussion of the different enhancement mechanisms.

show abstract

Enhancement of Raman scattering in dielectric nanostructures with electric and magnetic Mie resonances

Cited by 46 publications

References 33 publications

Using optical resonances to control heat generation and propagation in silicon nanostructures

Using optical resonances to control heat generation and propagation in silicon nanostructures

Probing optical resonances of silicon nanostructures using tunable-excitation Raman spectroscopy

Lattice Resonances and Local Field Enhancement in Array of Dielectric Dimers for Surface Enhanced Raman Spectroscopy

Contact Info

Product

Resources

About