Enhanced Five-Photon Photoluminescence in Subwavelength AlGaAs Resonators

Abstract

Multiphoton processes of absorption photoluminescence have enabled a wide range of applications including three-dimensional microfabrication, data storage, and biological imaging. While the applications of two-photon and three-photon absorption and luminescence have matured considerably, higher-order photoluminescence processes remain more challenging to study due to their lower efficiency, particularly in subwavelength systems. Here, we report the observation of five-photon luminescence from a single subwavelength nanoantenna at room temperature enabled by the Mie resonances. We excite an AlGaAs resonator at around 3.6 μm and observe photoluminescence at around 740 nm. We show that the interplay of the Mie multipolar modes at the subwavelength scale can enhance the efficiency of the five-photon luminescence by at least 4 orders of magnitude, being limited only by sensitivity of our detector. Our work paves the way toward applications of higher-order multiphoton processes at the subwavelength scales enabled by the physics of Mie resonances.

High-harmonic generation from a subwavelength dielectric resonator

“…Our calculations suggest that, in such resonators, the fourth harmonic intensity would be comparable to the ninth harmonic, which is below our detection limit. We note that similar single subwavelength resonators were shown to produce enhanced multiphoton luminescence enhanced by Mie resonances when excited with linear polarization ( 28 ).…”

“…The optical properties for ITO are included by the ADE technique to FDTD Maxwell solver (34), considering the dispersion relation with λ ENZ = 1.25 μm from (28). For the central wavelength λ = 3.75 μm corresponding to the resonant excitation of the nanodisk, the other nonexcited materials are transparent, and their permittivities are given by ε AlGaAs ~3.1 2 , ε Al2O3 ~1.7 2 , and ε SiO2 ~1.4 2 .…”

“…We note that the Q factor of a realistic subwavelength resonator stays finite, and therefore the modes associated with the BICs are known as quasi-BICs. Single nanoparticles hosting such modes have demonstrated enhancement of second harmonic generation ( 4 ) as well as multiphoton luminescence ( 28 ). Recent theoretical predictions suggested the enhancement of both direct and cascaded generation of fifth harmonic in quasi-BIC nanoparticles ( 29 ).…”

Deep‐Subwavelength Resonant Meta‐Optics Enabled by Ultra‐High Index Topological Insulators

“…[9][10][11] All-dielectric structures inherently support both electric and magnetic multipole excitations, [11] enable a convenient platform for active tunability through various physical phenomena, [7,12,21,[13][14][15][16][17][18][19][20] and can easily be integrated with existing technologies and CMOS fabrication processes. [1] A rich library of optical functionalities has been demonstrated in various platforms such as spectral and spatial filtering, [6,7,[22][23][24][25] polarization control, [26,27] beam focusing, [28][29][30][31][32] beam deflectors, [33][34][35] holograms, [36,37] image processing, [38][39][40] and nonlinear phenomena, [41][42][43][44][45] to name a few. In most cases, extensively studied semiconductor materials are being used, having moderately high refractive indices such as Si (n ≈ 3.7), [16] GaAs (3.5), and Ge (n ≈ 4), [12] whereas...…”

Spectral Tuning of High‐Harmonic Generation with Resonance‐Gradient Metasurfaces

“…[8][9][10]) and third-harmonics generation (see, e.g., Refs. [11][12][13][14]) toward the studies of nonperturbative nonlinear regimes of light-matter interaction including multi-photon absorption [15] and high-harmonic generation. [16][17][18][19][20][21] Nanoparticles with carefully engineered geometries can support optical modes empowered by Mie resonances, such as optically-induced magnetic dipole resonances, [11] higher-order multipoles, [22] and anapole states, [13] as well as extended lattice modes associated with Fano resonances [12] and bound states in the continuum.…”