Second-harmonic generation in periodically poled silicon waveguides with lateral p-i-n junctions

Abstract

Electric-field-induced second-harmonic generation is demonstrated in silicon waveguides with reverse biased lateral p-i-n junctions. Phase matching is achieved by periodically poling the applied electric field. Two different poling configurations are compared: in the first, the p- and n-type doped regions of the junctions are on different sides of the waveguide (simple configuration), while in the second, they are alternated periodically across the waveguide sides (interdigitated configuration). Both simulations and experiments show that the generation efficiency is increased by 10 times comparing the interdigitated and simple configurations. The effective second-order susceptibility modulation obtained at a reverse bias voltage of 3.5 V is Δ χ e f f , S ( 2 ) ≃ 0.14 p m / V for the simple configuration and Δ χ e f f , I ( 2 ) ≃ 0.64 p m / V for the interdigitated one.

Thirty Years in Silicon Photonics: A Personal View

“…From Ref. [192]. (I) The FWM conversion efficiency of the photonic molecule (blue curve), as a function of the phase ϕ, is compared to the one of the critically coupled All-Pass (red curve) and Add-Drop (green curve) resonators, and to the one of the Add-Drop resonators which form the molecule (black curve).…”

“…Noticeably, if a static E DC induces a χ (2) eff , a large nonlinearity should be observed in a waveguide embedded in a p-i-n diode. Indeed, this is the case [192]. p-i-n junctions were fabricated across a silicon rib waveguide.…”

Tailoring Third Harmonic Generation From Anapole Mode in a Metal-Dielectric Hybrid Nanoantenna

“…As one of its branches, nonlinear nanophotonics aims to manipulate the interaction between light and matter in a nonlinear manner at the nanoscale [1]. By exchanging energy between photons, various nonlinear responses, such as harmonic generation [2]- [5], spontaneous emission [6] and optical bistability [7], [8], etc., have been widely employed in frequency conversion [9], quantum sources [10] and biosensing [11].…”

Second Harmonic Generation in Germanium Quantum Wells for Nonlinear Silicon Photonics

“…Bulk Si and Ge are compatible with PIC foundry processes [10,11], however they feature vanishing second-order susceptibility χ (2) due to their centrosymmetric unit cell. Several approaches have then been proposed to achieve second-order nonlinearities in silicon PICs: Electric field bias can induce nonlinearity in periodically poled silicon-on-insulator (SOI) waveguides, however with a rather small χ (2) = 0.64 pm/V [12]; SHG has been observed in Si3N4 waveguides on SiOx featuring χ (2) = 2.5 pm/V [13], and more recently in micro-resonators [14]. The transparency range of both SOI and Si3N4 waveguides is however limited to wavelengths λ < 4 μm as a result of the strong phonon absorption of SiOx [15,16,17].…”

“…Bulk Si and Ge are compatible with PIC foundry processes, , however, they feature vanishing second-order susceptibility χ (2) due to their centrosymmetric unit cell. Several approaches have then been proposed to achieve second-order nonlinearities in silicon PICs: Electric field bias can induce nonlinearity in periodically poled silicon-on-insulator (SOI) waveguides, however, with a rather small χ (2) = 0.64 pm/V; SHG has been observed in Si 3 N 4 waveguides on SiO x featuring χ (2) = 2.5 pm/V, and more recently in microresonators . The transparency range of both SOI and Si 3 N 4 waveguides is, however, limited to wavelengths λ < 4 μm as a result of the strong phonon absorption of SiO x . − Proposed unconventional approaches to generate optical nonlinearity in bulk Si include nanostructures with strain gradients, which are difficult to realize in a controlled manner, multiphoton absorption by impurities in Si, − which is, however, limited to the far-IR, and nonlinear free-electron plasma oscillations in heavily doped Si or Ge, which are accompanied by high ohmic losses.…”