The present disclosure relates to systems and methods relating to the fabrication of light guide elements. An example system includes an optical component configured to direct light emitted by a light source to illuminate a photoresist material at one or more desired angles so as to expose an angled structure in the photoresist material. The photoresist material overlays at least a portion of a first surface of a substrate. The optical component includes a container containing a light-coupling material that is selected based in part on the one or more desired angles. The system also includes a reflective surface arranged to reflect at least a first portion of the emitted light to illuminate the photoresist material at the one or more desired angles.

A device includes a substrate and nanoscale fin formed from a first material, a RF emitter that emits energy in a range of radio frequencies, and a waveguide formed from a second material. The device further includes a bichromatic directional coupler configured to couple pump and probe laser light into the waveguide. The waveguide is positioned proximate to the nanoscale fin along a coupling length such that the pump laser light propagating within the waveguide is coupled into the nanoscale fin from evanescent wave overlap along the coupling length. The pump laser light causes the first material to absorb the probe laser light when energy emitted by the RF emitter is at one or more frequencies dependent on a magnetic field. The device further includes a processor configured to determine a magnetic field strength of the magnetic field based on an identification of the one or more frequencies.

Disclosed is a method for fabricating a spherical concave mirror in an optical waveguide based on ultraviolet (UV) grayscale lithography. A key component is a specially designed mask pattern composed of a rectangle as well as a semicircle adjacent to the rectangle, where a rectangular area has no grayscale distribution, and UV light penetrating through different portions of the rectangular area has the same intensity; a semicircular area has the grayscale distribution, and the UV light penetrating through the semicircular area with the grayscale distribution is changed in intensity from the center of a circle in the radius direction according to a special function distribution law; an interlayer photoresist in the rectangular area is irradiated by the UV light penetrating through a mask plate and is developed to form an optical waveguide core.

A method for manufacturing a waveguide aperture to block stray light from a facet of an integrated optical device include obtaining a wafer with one or more integrated optical devices formed thereon and with a cleaved facet; positioning a mask in front of the cleaved facet, thereby masking at least a portion of the waveguide aperture of at least one the one or more integrated optical devices; and applying a light-blocking coating to the cleaved facet with the mask masking the portion of each of the one or more integrated optical devices.

A device providing efficient transformation between an initial optical mode and a second optical mode includes first, second and third elements fabricated on a common substrate. The first element includes first and second active sub-layers supporting initial and final optical modes with efficient mode transformation therebetween. The second element includes a passive waveguide structure supporting a second optical mode. The third element, at least partly butt-coupled to the first element, includes an intermediate waveguide structure supporting an intermediate optical mode. If the final optical mode differs from the second optical mode by more than a predetermined amount, a tapered waveguide structure in the second or third elements facilitates efficient transformation between the intermediate optical mode and the second optical mode. Precise alignment of sub-elements formed in one of the elements, relative to sub-elements formed in another one of the elements, is defined using lithographic alignment marks.

Integrated optical devices and methods of forming the same are disclosed. A method of forming an integrated optical device includes the following steps. A substrate is provided. The substrate includes, from bottom to top, a first semiconductor layer, an insulating layer and a second semiconductor layer. The second semiconductor layer is patterned to form a waveguide pattern. A surface smoothing treatment is performed to the waveguide pattern until a surface roughness Rz of the waveguide pattern is equal to or less than a desired value. A cladding layer is formed over the waveguide pattern.

The present disclosure relates to semiconductor structures and, more particularly, to rib waveguide structures and methods of manufacture. The structure includes: a waveguide structure comprising one or more bends, an input end and an output end; and grating structures which are positioned adjacent to the one or more bends of the waveguide structure.

Structures for a waveguide bend and methods of fabricating a structure for a waveguide bend. A waveguide core has a first section, a second section, and a waveguide bend connecting the first section with the second section. The waveguide core includes a first side surface extending about an inner radius of the waveguide bend and a second side surface extending about an outer radius of the waveguide bend. A curved strip is arranged over the waveguide bend adjacent to the first side surface or the second side surface.

An optical device comprises first, second and third elements fabricated on a common substrate. The first element comprises an active waveguide structure supporting a first optical mode, the second element comprises a passive waveguide structure supporting a second optical mode, and the third element, at least partly butt coupled to the first element, comprises an intermediate waveguide structure supporting intermediate optical modes. If the first optical mode differs from the second optical mode by more than a predetermined amount, a tapered waveguide structure in at least one of the second and third elements facilitates efficient adiabatic transformation between the second optical mode and one of the intermediate optical modes. No adiabatic transformation occurs between any of the intermediate optical modes and the first optical mode. Mutual alignments of the first, second and third elements are defined using lithographic alignment marks.

An optical element has a substrate; and first to third optical waveguides formed on the substrate and each having a lower clad layer, a core layer, and an upper clad layer, the core layer having a larger refractive index than the lower clad layer and the upper clad layer. The first optical waveguide is optically connected to the second optical waveguide, and the second optical waveguide is optically connected to the third optical waveguide. The first to third optical waveguides have a mesa structure formed in a mesa shape in which at least the upper clad layer and an upper part of the core layer project above the lower clad layer. The core height of the third optical waveguide is lower than the core height of the first optical waveguide. The mesa width of the third optical waveguide is narrower than the mesa width of the first optical waveguide.