Electric field-induced second-order nonlinear optical effects in silicon waveguides

By Erman Timurdogan, Christopher V. Poulton, Matthew J. Byrd, M. Watts. Nature Photonics, 2016

272 citations recorded by the source corpus.

The symmetry of crystalline silicon inhibits a second-order optical nonlinear susceptibility, χ(2), in complementary metal–oxide–semiconductor-compatible silicon photonic platforms. However, χ(2) is required for important processes such as phase-only modulation, second-harmonic generation (SHG) and sum/difference frequency generation. Here, we break the crystalline symmetry by applying direct-current fields across p–i–n junctions in silicon ridge waveguides and induce a χ(2) proportional to the large χ(3) of silicon. The obtained χ(2) is first used to perturb the permittivity (the direct-current Kerr effect) and achieve phase-only modulation. Second, the spatial distribution of χ(2) is altered by periodically patterning p–i–n junctions to quasi-phase-match pump and second-harmonic modes and realize SHG. We measure a maximum SHG efficiency of P2ω/Pω2 = 13 ± 0.5% W−1 at λω = 2.29 µm and with field-induced χ(2) = 41 ± 1.5 pm V–1. We expect such field-induced χ(2) in silicon to lead to a new class of complex integrated devices such as carrier-envelope offset frequency stabilizers, terahertz generators, optical parametric oscillators and chirp-free modulators. The application of d.c. fields across p–i–n junctions in silicon ridge waveguides leads to crystal symmetry breaking. This induces a second-order optical nonlinear susceptibility that enables phase-only modulation and second-harmonic generation with an efficiency of ∼13% W–1 at 2.29 µm.

Subfields: Atomic and Molecular Physics, and Optics, Electrical and Electronic Engineering

View Paper: https://www.semanticscholar.org/paper/e011b840cbdda4220e0bc5606fa2105d73ffe31f

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Atomic and Molecular Physics, and Optics

In Electrical and Electronic Engineering

Citations in the corpus

Silicon Quantum Photonics (2015, methodology): “This latter approach has been demonstrated in a reverse-biased PIN modulator [105], using standard silicon manufacturing techniques.”
Linear programmable nanophotonic processors (2018, background): “Lossless phase shifting mechanisms in silicon include the thermooptic effect (3 dB bandwidth up to a few hundred kilohertz) [29], mechanical effects (∼MHz bandwidth) [30,31], and electricfield-induced electro-optic effects (∼GHz bandwidth) [32].”