All-Optical Modulation in Chains of Silicon Nanoantennas

Abstract

Dielectric nanoantennas represent a new branch of nanophotonics that allows efficient control of light scattering at nanoscale. Coupled nanoantennas can guide light on a chip over large distances without radiation losses, enabling a new nanoantenna-based silicon photonics platform with enchanced functionalities for light-on-chip integration. Here, an all-optical on-chip modulator based on a one-dimensional chain of silicon nanoantennas is proposed and experimentally demonstrated in the 1.55 μm telecommunication wavelength range. A resonator, with a quality factor up to 10 4 , is designed on the basis of a chain of coupled silicon nanoantennas, each supporting the electric dipole Mie resonance. Wafer-level fabrication of the nanoantennas is realized using CMOS compatible photolithography. High-speed modulation of the cavity mode is experimentally demonstrated via optical injection of free electrons and holes using a pulsed laser. The modulator is shown to have a response time of 50 ps and modulation depth beyond 25 dB, with 10 dB switching power being as low as ∼50 fJ. Low power and high-speed switching of the proposed device combined with the large-scale fabrication capabilities pave the way to applications of this dielectric nanoantenna-based approach to industrial on-chip photonics.

High-Q Dielectric Mie-Resonant Nanostructures (Brief Review)

“…Mie resonances open new opportunities to control light at the nanoscale, and they can support slow-light waveguiding in a chain of coupled Mieresonant silicon nanoparticles at telecommunication wavelengths. Recent studies demonstrated experimentally the opportunities and advantages of these novel types of subwavelength waveguides and their applications [27,28].…”

“…Figure 1(a-e) show the examples of the SEM images (adopted from Refs. [6][7][8][9][10]) of several types of dielectric structures. In particular, subwavelength optical antennas made of high-index dielectric materials can have various shapes such cubes and cylinders [see Figs.…”

Coherent Networks of Si Nanocrystals: Tunable Collective Resonances with Narrow Spectral Widths

“…[ 25–27 ] Recent studies have highlighted the application of 1D chains of Si NCs for resonant guiding of light [ 30 ] and on‐chip modulators in the 1.55 mm range. [ 31 ] Periodic structures of high‐index dielectric nanoparticles have also gained significant attention. Recent studies have shown the possibility of hybridization of magnetic and electric dipoles of Si nanoparticles with the lattice modes, forming SLRs associated with diffractive coupling of such dipoles with the Rayleigh anomaly (RA).…”

Unidirectional coupling of a quantum emitter to a subwavelength grating waveguide with engineered stationary inflection point

“…This includes single nanoantennas and their ensembles for control of the QE luminescence radiation patterns, [26][27][28][29][30] optical cavities and waveguides composed of dielectric and semiconductor nanoparticles for the Purcell enhancement and lasing, [31][32][33][34] as well as active metasurfaces. 35,36 In this context, periodic dielectric waveguides provide vast opportunities for dispersion engineering [37][38][39] and achieving slow light regimes for efficient modulation of optical signals 40 as well as polarization control due to the mode degeneracy engineering. [41][42][43] In this work, we propose an approach for the design of an optical nanostructure based on a periodic waveguide that can serve as an efficient chiral interface between the propagating waveguide modes and the circularly polarized dipole sources embedded in the structure.…”