In one example embodiment, an integrated silicon photonic wavelength division demultiplexer includes an input waveguide, an input port, a plurality of output waveguides, a plurality of output ports, a first auxiliary waveguide, and a plurality of auxiliary waveguides. The input waveguide may be formed in a first layer and having a first effective index n1. The input port may be optically coupled to the input waveguide. The output waveguides may be formed in the first layer and may have the first effective index n1. Each of the output ports may be optically coupled to a corresponding output waveguide. The first auxiliary waveguide may be formed in a second layer below the input waveguide in the first layer. The first auxiliary waveguide may have a second effective index n2 and may have two tapered ends, and n2 may be higher than n1.

An apparatus includes a planar structure having a top surface, a bottom surface, and an edge; and an optical grating located near or at the top surface and having a regular pattern of features. The planar structure has a cavity, and a portion of the cavity is located between opposing portions of the top and bottom surfaces. The optical grating is adjacent to the edge and is over, at least a part of the cavity. The apparatus includes an optically reflective coating on a portion of a wall of the cavity below the optical grating. The cavity has an opening along a portion of the edge of the planar structure.

An apparatus includes a planar structure having a top surface, a bottom surface, and an edge; and an optical grating located near or at the top surface and having a regular pattern of features. The planar structure has a cavity, and a portion of the cavity is located between opposing portions of the top and bottom surfaces. The optical grating is adjacent to the edge and is over, at least a part of the cavity. The apparatus includes an optically reflective coating on a portion of a wall of the cavity below the optical grating. The cavity has an opening along a portion of the edge of the planar structure.

A method of forming a wedge-shaped fiber array and a bottom base according to a probing pad layout of a Si-Photonic device to enable optical, DC and RF mixed signal tests to be performed at the same time and the resulting device are provided. Embodiments include a bottom base; and a fiber array with sidewalls and a top surface having a first angle and a second angle, respectively, over the bottom base, wherein the fiber array is structured to expose bond pads of a Si-Photonic device during wafer level Si-Photonic testing.

An optical waveguide structure includes a lower cladding layer positioned on a substrate; an optical guide layer positioned on the lower cladding layer; an upper cladding layer positioned on the optical guide layer; and a heater positioned on the upper cladding layer. The lower cladding layer, the optical guide layer, and the upper cladding layer constitute a mesa structure. The optical guide layer has a lower thermal conductivity than the upper cladding layer. An equation W.sub.wgW.sub.mesa3W.sub.wg is satisfied, wherein W.sub.mesa represents a mesa width of the mesa structure, and W.sub.wg represents a width of the optical guide layer. The optical guide layer occupies one-third or more of the mesa width in a width direction of the mesa structure.

One example includes a photodetector system. The system includes a waveguide photodetector into which an input optical signal comprising a frequency band of interest is provided and from which the input optical signal is absorbed to generate an output signal that is indicative of an intensity of the input optical signal. The system also includes a reflector coupled to the waveguide photodetector and which is to reject frequencies outside of the frequency band of interest and to reflect the frequency band of interest back into the waveguide photodetector.

One example includes a photodetector system. The system includes a waveguide photodetector into which an input optical signal comprising a frequency band of interest is provided and from which the input optical signal is absorbed to generate an output signal that is indicative of an intensity of the input optical signal. The system also includes a reflector coupled to the waveguide photodetector and which is to reject frequencies outside of the frequency band of interest and to reflect the frequency band of interest back into the waveguide photodetector.

Hybrid optical integration places very strict manufacturing tolerances and performance requirements upon the multiple elements to exploit passive alignment techniques as well as having additional processing requirements. Alternatively, active alignment and soldering/fixing where feasible is also complex and time consuming with 3, 4, or 6-axis control of each element. However, microelectromechanical (MEMS) systems can sense, control, and activate mechanical processes on the micro scale. Beneficially, therefore the inventors combine silicon MEMS based micro-actuators with silicon CMOS control and drive circuits in order to provide alignment of elements within a silicon optical circuit either with respect to each other or with other optical elements hybridly integrated such as compound semiconductor elements. Such inventive MEMS based circuits may be either maintained as active during deployment or powered off once the alignment has been locked through an attachment/retention/latching process.

Hybrid optical integration places very strict manufacturing tolerances and performance requirements upon the multiple elements to exploit passive alignment techniques as well as having additional processing requirements. Alternatively, active alignment and soldering/fixing where feasible is also complex and time consuming with 3, 4, or 6-axis control of each element. However, microelectromechanical (MEMS) systems can sense, control, and activate mechanical processes on the micro scale. Beneficially, therefore the inventors combine silicon MEMS based micro-actuators with silicon CMOS control and drive circuits in order to provide alignment of elements within a silicon optical circuit either with respect to each other or with other optical elements hybridly integrated such as compound semiconductor elements. Such inventive MEMS based circuits may be either maintained as active during deployment or powered off once the alignment has been locked through an attachment/retention/latching process.

Embodiments herein describe a photonic chip which includes a coupling interface for evanescently coupling the chip to a waveguide on an external substrate. In one embodiment, the photonic chip includes a tapered waveguide that aligns with a tapered waveguide on the external substrate. The respective tapers of the two waveguides are inverted such that as the width of the waveguide in the photonic chip decreases, the width of the waveguide on the external substrate increases. In one embodiment, these two waveguides form an adiabatic structure where the optical signal transfers between the waveguides with minimal or no coupling of the optical signal to other non-intended modes. Using the two waveguides, optical signals can be transmitted between the photonic chip and the external substrate.