A photonic chip and a preparation method thereof are provided. The chip includes a lithium niobate film modulator array, a first optical coupling array, and a silica waveguide wavelength-division multiplexer, and the lithium niobate film modulator array includes one or more lithium niobate film modulators and is used to modulate an optical signal; the first optical coupling array includes one or more first optical coupling structures, and the first optical coupling structure has one end connected to a corresponding lithium niobate thin film modulator and the other end connected to the silica waveguide wavelength-division multiplexer so as to transmit the modulated optical signal to the silica waveguide wavelength-division multiplexer; and the silica waveguide wavelength-division multiplexer is used to perform wavelength-division multiplexing on the modulated optical signal.

A hybrid photonic chip comprising a plurality of semiconductor materials arranged to define a chip providing a function, wherein at least a first part of the chip is formed of materials which can be fabricated using a CMOS technique; and at least a second part of the chip which comprises non-linear crystal material and is not subjected to etching process; wherein the second part of the chip in conjunction with the first part is configured to support a propagating low loss single mode.

In an example, an integrated optical circuit (IOC) includes a first substrate formed of a first material and a first waveguide formed of a second material and positioned on the first substrate. The first waveguide includes a plurality of branches and is configured to polarize light beams that propagate through the first waveguide. The IOC further includes a second substrate formed of a third material, the second substrate coupled to or positioned on the first substrate. The IOC further includes a plurality of straight waveguides formed in the second substrate, each of the plurality of straight waveguides optically coupled to a respective branch of the plurality of branches of the first waveguide. The IOC further includes a plurality of electrodes positioned proximate to the plurality of straight waveguides, the plurality of electrodes configured to modulate the phase of light beams that propagate through the plurality of straight waveguides.

An optical waveguide device including a rib-type optical waveguide 2 formed of a material having an electro-optic effect, and a reinforcing substrate 1 that supports the rib-type optical waveguide, one end of the rib-type optical waveguide 2 has a tapered portion 20, structures 4 are provided that are disposed apart from the tapered portion so as to sandwich the tapered portion and are disposed on the reinforcing substrate 1, an upper substrate is disposed above the tapered portion and the structures, and an adhesive layer is disposed in a space sandwiched between the upper substrate and the structures.

An optical device includes a substrate, a layered structure provided on the substrate and including an intermediate layer, an optical waveguide formed of a thin crystal film having an electro-optic effect, and a buffer layer stacked in this order, and an electrode provided on or above the buffer layer and configured to apply a direct current voltage to the optical waveguide. The resistivity of the intermediate layer is higher than the resistivity of the buffer layer.

Techniques regarding quantum transducers are provided. For example, one or more embodiments described herein can include an apparatus that can include a superconducting microwave resonator having a microstrip architecture that includes a dielectric layer positioned between a superconducting waveguide and a ground plane. The apparatus can also include an optical resonator positioned within the dielectric layer.

An optical coupling structure, an optical coupling system and a method for preparing the optical coupling structure are provided. The method includes: step S101: preparing a base substrate; step S102: forming a lithium niobate optical waveguide on the base substrate; step S103: forming a silicon dioxide core layer enclosing the lithium niobate optical waveguide on peripheral walls of the lithium niobate optical waveguide; step S104: forming a silicon dioxide cladding layer enclosing the silicon dioxide core layer on peripheral walls of the silicon dioxide core layer. The optical coupling structure alleviates a technical problem of low coupling efficiency between the lithium niobate optical waveguide and the single-mode optical fiber in the related art, and achieves a technical effect of improving the coupling efficiency between the lithium niobate optical waveguide and the single-mode optical fiber.

Photonic integrated circuits utilizing interferometric effects, such as wavelength multiplexers/demultiplexers, include a free-space coupling region having two core layers that have thermo-optic coefficients of opposite sign. The two core layers are configured to provide athermal or nearly-athermal operation. Described examples include integrated array waveguide grating devices and integrated echelle grating devices. Example material systems include LNOI and SOI.

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, fabricated on a planarized top surface of the first 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, positioned such that a top surface of the intermediate structure underlies a bottom surface of the passive waveguide structure. 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 first optical mode and the second optical mode. Mutual alignments of the first, second and third elements are defined using lithographic alignment marks.

An integrated optical device includes a substrate. A waveguide includes a lithium niobate. A TiO.sub.2 coating is disposed at least in part over a longitudinal surface of the waveguide as a coated waveguide supported by the substrate. A silicon oxide substantially can cover and surround the waveguide in cross section over a longitudinal direction of said waveguide as an optical cladding. A method for substantially eliminating optical damage in lithium niobate devices is also described.