An example system includes a grating coupled laser, a laser optical interposer (LOI), an optical isolator, and a light redirector. The grating coupled laser includes a laser cavity and a transmit grating optically coupled to the laser cavity. The transmit grating is configured to diffract light emitted by the laser cavity out of the grating coupled laser. The LOI includes an LOI waveguide with an input end and an output end. The optical isolator is positioned between the surface coupled edge emitting laser and the LOI. The light redirector is positioned to redirect the light, after the light passes through the optical isolator, into the LOI waveguide of the LOI.

In an example, an Echelle grating wavelength division multiplexing (WDM) device includes a first waveguide, a slab waveguide, multiple second waveguides, an Echelle grating, and a metal-filled trench. The first waveguide includes either an input waveguide or an output waveguide. The multiple second waveguides are optically coupled to the first waveguide through the slab waveguide. The multiple second waveguides include multiple output waveguides if the first waveguide includes the input waveguide or multiple input waveguides if the first waveguide includes the output waveguide. The Echelle grating includes multiple grating teeth formed in the slab waveguide. The metal-filled trench forms a mirror at the grating teeth to reflect incident light from the first waveguide toward the multiple second waveguides or from the multiple second waveguides toward the first waveguide.

In an example, an Echelle grating wavelength division multiplexing (WDM) device includes a first waveguide, a slab waveguide, multiple second waveguides, an Echelle grating, and a metal-filled trench. The first waveguide includes either an input waveguide or an output waveguide. The multiple second waveguides are optically coupled to the first waveguide through the slab waveguide. The multiple second waveguides include multiple output waveguides if the first waveguide includes the input waveguide or multiple input waveguides if the first waveguide includes the output waveguide. The Echelle grating includes multiple grating teeth formed in the slab waveguide. The metal-filled trench forms a mirror at the grating teeth to reflect incident light from the first waveguide toward the multiple second waveguides or from the multiple second waveguides toward the first waveguide.

A spot-size converter includes a first part of a waveguiding structure to couple to a first waveguide to receive light from or transmit light to the first waveguide in a first propagation mode, wherein the first part of the waveguiding structure has a lower waveguiding structure with a varying effective refractive index that decreases away from the first waveguide; and a second part of the waveguiding structure to couple to a second waveguide to transmit light to or receive light from the second waveguide in a second propagation mode, the second part of the waveguiding structure includes an upper waveguiding structure with a plurality of high-index elements arranged therein, an overlap region is between the first part and the second part, the first propagation mode progressively transforms into the second propagation mode in the overlap region.

A spot-size converter includes a first part of a waveguiding structure to couple to a first waveguide to receive light from or transmit light to the first waveguide in a first propagation mode, wherein the first part of the waveguiding structure has a lower waveguiding structure with a varying effective refractive index that decreases away from the first waveguide; and a second part of the waveguiding structure to couple to a second waveguide to transmit light to or receive light from the second waveguide in a second propagation mode, the second part of the waveguiding structure includes an upper waveguiding structure with a plurality of high-index elements arranged therein, an overlap region is between the first part and the second part, the first propagation mode progressively transforms into the second propagation mode in the overlap region.

An integrated wavelength division multiplexing (WDM) optical transceiver comprises the following elements: (1) a light source; (2) an array of photodiodes responsive to a plurality of optical signals and forming a plurality of electrical received information signals therefrom; and (3) a photonics integrated module (PIM) including transmission components and receiving components necessary to provide transceiver functionality. The transmission components include a demultiplexer, an electro-optic modulator array, and a multiplexer for combining a plurality of modulated optical signals onto a single output signal path as the transceiver output. The receiving components include a demultiplexer responsive to an incoming WDM signal for separating each wavelength component and creating a plurality of received optical signals.

An integrated wavelength division multiplexing (WDM) optical transceiver comprises the following elements: (1) a light source; (2) an array of photodiodes responsive to a plurality of optical signals and forming a plurality of electrical received information signals therefrom; and (3) a photonics integrated module (PIM) including transmission components and receiving components necessary to provide transceiver functionality. The transmission components include a demultiplexer, an electro-optic modulator array, and a multiplexer for combining a plurality of modulated optical signals onto a single output signal path as the transceiver output. The receiving components include a demultiplexer responsive to an incoming WDM signal for separating each wavelength component and creating a plurality of received optical signals.

A millimeter scale weak grating coupler comprising a silicon waveguide having bars of overlay material of length (a) disposed periodically at a period () adjacent the silicon waveguide whereby a uniform grating output is achieved.

A millimeter scale weak grating coupler comprising a silicon waveguide having bars of overlay material of length (a) disposed periodically at a period () adjacent the silicon waveguide whereby a uniform grating output is achieved.

An optical waveguide (10) includes a substrate (15), a core layer (11) that extends along the longitudinal direction and through which infrared light IR can propagate, and a support (17) formed from a material with a smaller refractive index than the core layer (11) and configured to connect at least a portion of the substrate (15) and at least a portion of the core layer (11) to support the core layer with respect to the substrate (15). A connecting portion (171) of the support (17) connected to the core layer (11) is shifted from the position having the shortest distance from the center to the outer surface in a cross-section perpendicular to the longitudinal direction of the core layer (11).