A fiber-to-fiber system for multi-layer ferroelectric on insulator waveguide devices is described. The system comprises a fiber-to-chip coupler that couples light from a standard optical fiber to multi-layer ferroelectric on insulator waveguides. The multi-layer ferroelectric on insulator waveguides are integrated with electrodes to implement an optical device, an electro-optical device, or a non-linear optical device, such as an electro-optical modulator, with microwave and optical waveguide crossings compatible with packaging. A second fiber-to-chip coupler outputs the light from the multi-layer ferroelectric on insulator device to a standard optical fiber.

Provided is an optical scanning element, which has a large scan angle, is quickly responsive, and can be downsized. The optical scanning element includes: a photonic crystal layer having holes periodically formed in an electro-optical crystal substrate; a line-defect optical waveguide formed in the photonic crystal layer; a diffraction grating arranged in at least one portion selected from an upper portion, a left side surface portion, and a right side surface portion of the optical waveguide; and electrodes arranged on a left side and a right side of the optical waveguide. The optical scanning element is configured so that an emission angle of light emitted from an upper surface of the optical waveguide is changed.

A optical device including: a substrate; an optical waveguide formed at the substrate; and a protective layer formed adjacent to the optical waveguide, wherein the optical waveguide includes multiple side surfaces that intersect the substrate, at least one side surface of the optical waveguide is provided with a rough surface. According to the optical device, the light propagation loss can be reduced.

An optical waveguide structure comprises a nonlinear optical waveguide, a set of tuning optical waveguides, a set of wavelength selective couplers that couples light between the nonlinear optical waveguide and one or more tuning optical waveguides in the set of tuning optical waveguide based on a wavelength of light, and a set of phase shifters located along one or more tuning optical waveguides in the set of tuning optical waveguides.

An optical modulator includes an optical modulation element including an optical waveguide formed on a substrate and a housing that accommodates the optical modulation element, the housing has a bottom surface wall having a quadrilateral shape in a plan view, first and second long side walls that are connected to two opposite edges of the bottom surface wall, and first and second short side walls that are shorter than the first and second long side walls and are connected to two other opposite edges of the bottom surface wall. An average wall thickness of the second long side wall is equal to or larger than an average wall thickness of the first long side wall. At least one of the first and second short side walls has an average thickness that is thinner than the average thickness of the first long side wall.

A Y-branch dual electro-optical phase modulator (YBDPM) has a stitched-in zinc oxide diffused waveguide. It is more vacuum stable and has higher resistance to photorefractive damage than currently used Ti-diffused waveguides. The YBDPM is useful in Fiber Optic Gyroscopes (FOG), especially in low frequencies applications.

A layered solid element includes a ferroelectric layer of a crystalline material Li.sub.1−x(Nb.sub.1−yTa.sub.y).sub.1+xO.sub.3+2x−z which has X- or 33° Y-orientation with respect to a substrate of the layered solid element. The ferroelectric layer is grown epitaxially from a buffer layer having of one of the chemical formulae L.sub.kNi.sub.rO.sub.1.5.Math.(k+r)+w or L.sub.n+1Ni.sub.nO.sub.3n+1+δ, where L is a lanthanide element. Such layered solid element may form a thin-film bulk acoustic resonator and be useful for integrated electronic circuits such as RF-filters, or guided optical devices such as integrated optical modulators.

An example method of forming a deterministic thin film from a crystal substrate is described herein. The method can include implanting ions into a surface of the crystal substrate to form a thin film crystal layer, and bonding the crystal substrate and a handle substrate to form a bilayer bonding interface between the crystal substrate and the handle substrate. The method can also include exfoliating the thin film crystal layer from the crystal substrate, patterning the thin film crystal layer to define a deterministic thin film, etching one or more trenches in the thin film crystal layer, etching the bilayer bonding interface via the one or more trenches, and releasing the deterministic thin film from the handle substrate.

An optical computation system includes a light source configured to produce a pump beam, an optical modulator configured to modulate the pump beam based on the modulation mask to generate a modulated beam, a non-linear medium configured to convert a portion of the modulated beam to a second harmonic (SH) beam and to produce an output including the SH beam and an unconverted portion of the pump beam, and a dichroic mirror configured to receive the output of the non-linear medium and to decouple the SH beam and the unconverted portion of the pump beam, a detector configured to detect a first optical power of the unconverted portion of the pump beam and to detect a second optical power of the SH beam, and a controller configured to generate an updated modulation mask based on the first and second optical powers for transmission to the optical modulator.

This optical modulation element includes a first optical waveguide, a second optical waveguide, a first electrode for applying an electric field to the first optical waveguide, and a second electrode for applying an electric field to the second optical waveguide. The first optical waveguide and the second optical waveguide each include a ridge-shaped portion protruding from a first surface of a lithium niobate film. A first interaction length L.sub.1 that is a length of a part of the first electrode overlapping the first optical waveguide in a longitudinal direction is 0.9 mm or more and 20 mm or less. A second interaction length L.sub.2 that is a length of a part of the second electrode overlapping the second optical waveguide in the longitudinal direction is 0.9 mm or more and 20 mm or less.