Recent advances in phase matching of second‐order nonlinearities in monolithic semiconductor waveguides

Abstract

Techniques used to assist phase matching of second-order nonlinearities in semiconductor waveguides are reviewed. The salient points of each method are highlighted, with their strengths and weaknesses with regard to various key applications discussed. Recent progress in these techniques is also reviewed. Emphasis is placed on two techniques, namely quasi-phase matching via domain disordering utilizing quantum well intermixing, and exact phase matching using Bragg reflection waveguides.The figure shows (a) An optical microscope image of an ion implantation mask used to fabricate gratings used for quasiphase matching, (b) a scanning electron micrograph of an ion implantation mask, (c) a scanning electron micrograph of a semiconductor ridge waveguide structure, and (d) an optical microscope image of group monolithic ring lasers designed for integration with quasiphase matched structures.

Difference Frequency Generation by Quasi-Phase Matching in Periodically Intermixed Semiconductor Superlattice Waveguides

“…Hence, artificial structures need to be implemented in order to meet the phase matching condition. There are several methods for achieving phase matching in III-V semiconductors [4] and thus far, difference frequency generation (DFG) has been demonstrated in formbirefringent GaAs/Al y O x waveguides [5], [6], wafer-bonded domain-reversal quasi-phase matching (QPM) waveguides [7], orientation-patterned GaAs QPM waveguides [8], and modal phase matching Bragg reflection waveguides [9]. These platforms generally have a number of limitations, particularly where the monolithic integration of active optical devices such as lasers for pumping is considered, including the use of complex fabrication processes, inherently high propagation losses, incompatibility of the wafer growth process with doped heterostructures, and higher-order modal requirements.…”

Optical frequency conversion in integrated devices [Invited]

“…Since it is a non-centrosymmetric medium (unlike silicon), it possesses even-order nonlinearities, with a relatively large value of χ (2) of about 200 pm/V [39]. Typically, the lower-order nonlinearities are stronger than the higher-order nonlinear interactions, and thus AlGaAs devices capable of SHG and DFG are regularly investigated [40].…”

“…In order to achieve highly efficient optical frequency conversion, several photonic structures have been developed so far, relying on stronger mode confinement, and thus higher power density (see, e.g., [30,[60][61][62]), material dispersion compensation (see, e.g., [30,63,64]), artificial phase matching in non-birefringent materials (see, e.g., [40,64]), etc. However, these structures also present some drawbacks.…”

“…A comprehensive discussion of these techniques may be found in Ref. [13,40]. Typically, these techniques require complex fabrication processes and/or waveguide structures that limit their potential for monolithic integration.…”

Directional quasi-phase matching AlGaAs waveguide microresonators for efficient generation of quadratic frequency combs

“…This platform is extensively used in numerous devices like waveguides, microresonators, lasers, amplifiers, and modulators. 7 Moreover, aluminum gallium arsenide (AlGaAs) has a strong quadratic nonlinear response, which makes it ideal for the development of nonlinear photonic devices. 8,9 Although it lacks of natural birefringence, phase matching in AlGaAs can be realized in alternative different ways, such as form-birefringence phase matching, modal phase matching, domain-reversal quasi-phase matching, and domain disordered quasi-phase matching.…”