An optical waveguide 15 includes a substrate 19, a core layer 12, a support 20, and a suppressing portion. The core layer 12 includes a light propagating portion 10 and a diffraction grating portion 11. The diffraction grating portion 11 includes a fine line pattern formed therein. The support 20 is made from a material having a smaller refractive index than a refractive index of the core layer 12. The support 20 supports the core layer 12 with respect to the substrate 19. The suppressing portion suppresses deformation of fine lines 13 that form the fine line pattern. The support 20 is not provided in an entire region between the light propagating portion 10 and the substrate 19 in a cross-section perpendicular to a longitudinal direction of the core layer 12 at least at a position in the longitudinal direction.

A photonic chip includes a device layer and a port layer, with an optical port located at the port layer. Inter-layer optical couplers are provided for coupling light between the device and port layers. The inter-layer couplers may be configured to couple signal light but block pump light or other undesired wavelength from entering the device layer, operating as an input filter. The port layer may accommodate other light pre-processing functions, such as optical power splitting, that are undesirable in the device layer.

A photonic chip includes a device layer and a port layer, with an optical port located at the port layer. Inter-layer optical couplers are provided for coupling light between the device and port layers. The inter-layer couplers may be configured to couple signal light but block pump light or other undesired wavelength from entering the device layer, operating as an input filter. The port layer may accommodate other light pre-processing functions, such as optical power splitting, that are undesirable in the device layer.

A synthesized grating is provided comprising a substrate/layer, and a plurality of alternating aperiodic non-uniform low and high index profiles on a surface of the substrate/layer defining a transmission/reflection spectrum for one of either single or multi-frequency operation of said grating in an optical cavity. A method is also provided for designing the synthesized grating, comprising determining a grating structure of given profiles through analysis of an optimized weighted sum and mapping the grating profile to said surface with the plurality of alternating non-uniform low and high index profiles. A distributed feedback laser is also provided having top, bottom and two sides, comprising a top electrode, a cladding layer disposed below the top electrode a bottom electrode, a substrate disposed above the bottom electrode, one of either an active or passive waveguide layer, a synthesized aperiodic grating layer providing distributed minors, and wherein the waveguide layer and synthesized aperiodic grating layer are disposed between said the substrate and cladding layer and are separated by a spacer layer.

A photonic integrated circuit for an interferometric sensor includes a first waveguide called sensitive arm wherein a first portion of the light radiation is propagated, the sensitive arm being exposed to a first ambient medium and to at least one compound to be detected inducing a modification of the local refractive index perceived by the evanescent part of the electromagnetic field of the first portion of the light radiation, and a second waveguide called reference arm wherein a second portion of the light radiation is propagated, an encapsulation layer encapsulating the reference arm, the encapsulation layer being impermeable to the compound or compounds to be detected, so that the reference arm is exposed only to a second ambient medium, substantially of the same nature as the first ambient medium and without the compound to be detected and interferometric sensor comprising a photonic integrated circuit according to the invention.

An optical inspection circuit includes an optical circuit to be inspected formed on a substrate, an input optical waveguide optically connected to the optical circuit, and an output optical waveguide optically connected to the optical circuit. The input optical waveguide is connected with a grating coupler for input. The grating coupler is connected with the input optical waveguide via a spot size conversion unit. The output optical waveguide is optically connected with a photodiode.

An optical inspection circuit includes an optical circuit to be inspected formed on a substrate, an input optical waveguide optically connected to the optical circuit, and an output optical waveguide optically connected to the optical circuit. The input optical waveguide is connected with a grating coupler for input. The grating coupler is connected with the input optical waveguide via a spot size conversion unit. The output optical waveguide is optically connected with a photodiode.

Disclosed is a laser device. The laser device includes a substrate, a pump light source which is disposed on the substrate and provided with a light emitting layer configured to generate pump light, and an upper waveguide which is disposed above the pump light source in a first direction and provided with an upper resonator configured to allow laser light to be generated and resonate by using the pump light.

In some examples, a method includes forming a material layer on a substrate, partially polymerizing a component of the material layer, to form fluid-filled droplets within a partially polymerized matrix, deforming the material layer to form anisotropic fluid-filled droplets, and further polymerizing the partially polymerized matrix to form an anisotropic voided polymer, including anisotropic voids in a polymer matrix. The anisotropic voids may include anisotropic nanovoids. Example methods may further include depositing electrodes on the anisotropic voided polymer so that at least a portion of the anisotropic voided polymer is located between the electrodes. Examples may include forming electroactive elements including an anisotropic nanovoided polymer, and devices (such as sensors and/or actuators) including electroactive elements.

In some examples, a device includes a multilayer structure, a first electrode, and a second electrode, where the multilayer structure is located at least in part between the first electrode and the second electrode, and the multilayer structure includes a nanovoided polymer layer, and a solid layer. The solid layer may include a non-nanovoided layer. The nanovoided polymer layer may be an electroactive layer. The device may further include a control circuit configured to apply an electrical potential between the first electrode and the second electrode, which may induce a mechanical deformation of the multilayer.