To provide a multiplexer that makes it possible to achieve a reduction in size and that minimizes the influence of the expansion of laser light on a multiplexing unit. A multiplexer is provided with a plurality of waveguides, multiplexing units that are provided at an intermediate location within the waveguides, and laser light sources, wherein: the first multiplexing unit is arranged at a position that is closest to the laser light sources; and the laser light sources that have an optical axis at a position that is separated from the transmission axis of the visible light that is introduced into the first multiplexing unit are arranged so that the optical axis is inclined with respect to the transmission axis and the outer periphery of laser light that expands at a predetermined expansion angle passes in front of the first multiplexing unit.

To provide a multiplexer that makes it possible to achieve a reduction in size and that minimizes the influence of the expansion of laser light on a multiplexing unit. A multiplexer is provided with a plurality of waveguides, multiplexing units that are provided at an intermediate location within the waveguides, and laser light sources, wherein: the first multiplexing unit is arranged at a position that is closest to the laser light sources; and the laser light sources that have an optical axis at a position that is separated from the transmission axis of the visible light that is introduced into the first multiplexing unit are arranged so that the optical axis is inclined with respect to the transmission axis and the outer periphery of laser light that expands at a predetermined expansion angle passes in front of the first multiplexing unit.

An integrated optical component includes at least one input waveguide, at least one output waveguide; a first slab waveguide having a first refractive index, n1. The first slab waveguide may be disposed between at least one of the input waveguides and at least one of the output waveguides. The integrated optical component may further include a second slab waveguide having a second refractive index, n2. The integrated optical component may also include a third cladding slab having a third refractive index, n3. The third cladding slab may be disposed between the first slab and the second slab. The thickness of the second slab waveguide and the thickness of the third slab waveguide are adjustable to reduce a birefringence of the integrated optical component.

An integrated optical component includes at least one input waveguide, at least one output waveguide; a first slab waveguide having a first refractive index, n1. The first slab waveguide may be disposed between at least one of the input waveguides and at least one of the output waveguides. The integrated optical component may further include a second slab waveguide having a second refractive index, n2. The integrated optical component may also include a third cladding slab having a third refractive index, n3. The third cladding slab may be disposed between the first slab and the second slab. The thickness of the second slab waveguide and the thickness of the third slab waveguide are adjustable to reduce a birefringence of the integrated optical component.

Methods and systems enable amplifying optical signals using a Bragg reflection waveguide (BRW) having second order optical nonlinearity to generate an optical pump by injection locking. The BRW may also be used for parametric amplification of optical signals using the optical pump. Feedback phase-power control may be performed to maximize output power.

Methods and systems enable amplifying optical signals using a Bragg reflection waveguide (BRW) having second order optical nonlinearity to generate an optical pump by injection locking. The BRW may also be used for parametric amplification of optical signals using the optical pump. Feedback phase-power control may be performed to maximize output power.

An electro-optic device may include a photonic chip having an optical grating coupler at a surface. The optical grating coupler may include a first semiconductor layer having a first base and first fingers extending outwardly from the first base. The optical grating coupler may include a second semiconductor layer having a second base and second fingers extending outwardly from the second base and being interdigitated with the first fingers to define semiconductor junction areas, with the first and second fingers having a non-uniform width. The electro-optic device may include a circuit coupled to the optical grating coupler and configured to bias the semiconductor junction areas and change one or more optical characteristics of the optical grating coupler.

An electro-optic device may include a photonic chip having an optical grating coupler at a surface. The optical grating coupler may include a first semiconductor layer having a first base and first fingers extending outwardly from the first base. The optical grating coupler may include a second semiconductor layer having a second base and second fingers extending outwardly from the second base and being interdigitated with the first fingers to define semiconductor junction areas, with the first and second fingers having a non-uniform width. The electro-optic device may include a circuit coupled to the optical grating coupler and configured to bias the semiconductor junction areas and change one or more optical characteristics of the optical grating coupler.

A coupling device including, integrated in or on a substrate, a waveguide capable of guiding a light beam centred on a central wavelength .sub.0 and an optical coupler. The waveguide and the optical coupler extend in two superposed stages of the coupling device. The optical coupler is composed of at least one index gradient structure. The average optical index in the index gradient structure varies monotonously, decreasing with increasing distance from the waveguide, the average optical index being an average value of the optical index in a cubic volume with a side dimension equal to:

[00001]$\frac{{}_0}{2*n_{\mathrm{eff}}}$

in which n.sub.eff is the effective index of guided mode in the waveguide.

A system includes a surface coupled edge emitting laser that includes a core waveguide, a fan out region optically coupled to the core waveguide in a same layer of the surface coupled edge emitting laser as the core waveguide; and a first surface grating formed in the fan out region; and a photonic integrated circuit (PIC) that includes an optical waveguide and a second surface grating formed in an upper layer of the PIC, wherein the second surface grating is in optical alignment with the first surface grating.