In one aspect, a photonic device includes a substrate layer comprising magnesium fluoride and an optical guiding layer disposed on the substrate layer. The optical guide layer includes silicon dioxide. The substrate layer and the optical guide layer are transparent at an ultraviolet and visible wavelength range. In another aspect, a method includes oxidizing silicon to form a silicon dioxide layer, bonding the silicon dioxide layer to magnesium fluoride, removing the silicon and performing lithography and etching of the silicon dioxide to form a photonic device.

Tapered waveguides made of high-index material attached to a tapered optical fiber are provided, enabling access to the optical modes of large, high-index resonators. In some embodiments, an optical fiber having a central axis, a tapered portion, and an untapered portion is provided. The tapered portion is configured to expose an evanescent field. An elongated waveguide is optically coupled to the optical fiber along the tapered portion and parallel to the central axis of the optical fiber. The elongated waveguide has a substantially triangular cross section perpendicular to the central axis of the optical fiber.

The invention describes an integrated photonics platform comprising a plurality of at least three vertically-stacked waveguides which enables light transfer from one waveguide of the photonic structure into another waveguide by means of controlled tunneling method. The light transfer involves at least three waveguides wherein light power flows from initial waveguide into the final waveguide while tunneling through the intermediate ones. As an exemplary realization of the controlled tunneling waveguide integration, the invention describes a photonic integrated structure consisting of laser guide as upper waveguide, passive guide as middle waveguide, and modulator guide as lower waveguides. Controlled tunneling is enabled by the overlapped lateral tapers formed on the same or different vertical waveguide levels. In the further embodiments, the controlled tunneling platform is modified to implement wavelength-(de)multiplexing, polarization-splitting and beam-splitting functions.

Provided is an optical fiber glass preform, in a preliminary step of a final drawing step, in which the optical fiber glass preform is undergone one or more drawing steps to be drawn to a final target diameter, wherein as an outer diameter of an effective portion of the glass preform is continuously measured in a longitudinal direction, and from outer diameter measurement results obtained, a regression line of y=ax+b is obtained using the least squares method with y as the outer diameter and x as a length, an absolute value of a slope a is less than or equal to 0.005 mm/mm; and a maximum value of an obtained absolute value of a curvature of the outer diameter at any given point, in the outer diameter measurement results obtained, is 0.003 or less.

Multilevel leaky-mode optical elements, including reflectors, polarizers, and beamsplitters. Some of the elements have a plurality of spatially modulated periodic layers coupled to a substrate. For infrared applications, the optical elements may have a bandwidth larger than 600 nanometers.

A method for fabricating an integrated semiconductor photonics device is disclosed. The method may include providing a first substrate having on its top surface a monocrystalline semiconductor layer suitable for supporting an optical mode and forming a homogenous and conformal first dielectric layer on a planar surface of the monocrystalline semiconductor layer. The method may further include providing a dielectric waveguide core on the first dielectric layer, the dielectric waveguide core optically coupled to a first region of the monocrystalline semiconductor layer through the first dielectric layer. The method may further include depositing a second dielectric layer on the dielectric waveguide core, thereby covering the dielectric waveguide core, and annealing the substrate to drive hydrogen out of the dielectric waveguide core.

The method for inscribing a waveguide into a media glass substrate generally has the steps of: relatively moving a femtosecond laser beam along a surface of the media glass substrate while maintaining the focus of the laser beam at a depth of less than the surface, wherein the waveguide has a loss of less than 0.2 dB/cm when measured at a wavelength of light signal propagating in the waveguide during normal use of the waveguide. Particularly, the method can have varying writing parameters according to whether the waveguide is single-mode or multi-mode.

The present invention provides three waveguide structures, including a protruding-type waveguide structure, a buried-type waveguide structure, and a redeposited-type waveguide structure, the protruding-type waveguide structure includes two axisymmetrically disposed first ends, and the first end is sequentially divided into a first region, a second region, and a third region in a direction toward an axis of symmetry; and the waveguide structure includes a first silicon substrate layer, a second silicon substrate layer, a first silicon dioxide layer, a second silicon dioxide layer, and a first silicon waveguide layer. The waveguide structure and the waveguide coupling structure that are provided in the present invention have advantages of a small size, low polarization dependence, and low temperature sensitivity, and a crosstalk value is greater than 25 dB, which meets a requirement of a passive optical network system, and provides feasibility for commercialization of the arrayed waveguide grating.

A device includes a substrate, a pedestal extending from the substrate, and a ring resonator disposed on the pedestal above the substrate. The ring resonator has a resonance wavelength greater than 1.5 μm and includes at least one of silicon and chalcogenide glass. The device can be used as a ring resonator sensor or a light source. The ring resonator is substantially transparent to mid-infrared radiation to reduce optical losses. The pedestal has a narrower width compared to the ring resonator to generate improved interaction between evanescent fields of light in the ring resonator and analytes nearby the ring resonator, thereby increasing sensing sensitivity. In addition, fabrication of the device is compatible with complementary metal-oxide-semiconductor (CMOS) processes and hence is amenable to large scale manufacturing.

After forming a first trench extending through a top semiconductor layer and a buried insulator layer and into a handle substrate of a semiconductor-on-insulator (SOI) substrate, a dielectric waveguide material stack including a lower dielectric cladding layer, a core layer and an upper dielectric cladding layer is formed within the first trench. Next, at least one lateral bipolar junction transistor (BJT), which can be a PNP BJT, an NPN BJT or a pair of complementary PNP BJT and NPN BJT, is formed in a remaining portion of the top semiconductor layer. After forming a second trench extending through the dielectric waveguide material stack to re-expose a portion of a bottom surface of the first trench, a laser diode is formed in the second trench.