155 results about "Effective refractive index" patented technology

The invention discloses a super-lens design method based on etching uniformity compensation and an optimization system thereof. The super-lens design method specifically comprises the following steps: S1, etching a wafer and establishing an etching rate space distribution model; S2, designing layout partitions and distributing compensation coefficients; s3, pre-compensating the size of the nano structure; s4, generating a final mask and executing etching; according to the method, the space size pre-compensation of the nano structure is actively performed in the mask design stage, and the phase deviation caused by non-uniform etching depth is counteracted by using the change of the effective refractive index of the nano unit, so that the high-performance super lens is obtained under the non-ideal process condition, and the limitation of the process physical limit is broken through.

An optical device includes a transition unit in which a first waveguide and a second waveguide are disposed in an overlapped manner such that a magnitude relationship of an effective refractive index between the vertical modes propagating the first waveguide and the vertical modes propagating the second waveguide is inverted at the positions of input and output. The transition unit allows, at the input, the second waveguide to be a single mode waveguide and allows, at the output, the second waveguide to be a multi-mode waveguide through which TM0 light in the maximum vertical mode and light in a higher-order mode propagate. The optical device includes a removing unit that allows the second waveguide to be a single mode waveguide through which the TM0 light propagates by removing the light in the higher-order mode from the light received from the transition unit.

An optical communication system can include a multiplexer / demultiplexer. The multiplexer / demultiplexer can transfer a first optical data signal between a first single-mode fiber and a first propagation mode of a few-mode fiber. The first propagation mode can have a first effective refractive index. The multiplexer / demultiplexer can transfer a second optical data signal between a second single-mode fiber and a combination of a second propagation mode of the few-mode fiber and a third propagation mode of the few-mode fiber. The second propagation mode and the third propagation mode can have a same effective refractive index that differs from the first effective refractive index. During propagation within the few-mode fiber, the second optical data signal can couple bidirectionally between the second propagation mode and the third propagation mode, while being substantially isolated from the first optical data signal in the first propagation mode.

The invention provides a novel perovskite cell and a preparation method thereof, the novel perovskite cell comprises an antireflection film stack layer, a glass substrate, an equivalent refraction layer, a hole transport layer, a perovskite layer, an electron transport layer and a top electrode which are arranged in sequence, the antireflection film stack layer is used for constructing refractive index transition between air and the glass substrate, and the hole transport layer is used for transmitting the hole transport layer. The absolute amount of effective light entering the battery is increased; the target effective refractive index of the equivalent refraction layer is associated with the first refractive index of the glass substrate and the second refractive index of the hole transport layer, and is used for constructing refractive index transition between the glass substrate and the hole transport layer so as to reduce the interface reflection loss of the perovskite cell; it is ensured that incident light passing through the glass substrate penetrates to the perovskite layer without significant loss. Through the superposition design, the utilization rate of light in the battery can be effectively improved, and the power generation efficiency of the battery is further improved.

The embodiment of the invention provides a multi-physical field collaborative simulation method and device for a high-speed silicon-based electro-optical modulator, and the method comprises the steps: building a physical model of the electro-optical modulator, carrying out the simulation under different bias voltage and temperature conditions, solving a Poisson equation, a carrier continuity equation and a drift diffusion transport equation, and obtaining the corresponding carrier concentration distribution; performing small-signal simulation analysis on the model to obtain corresponding PN junction electrical characteristic parameters; performing waveguide optical mode simulation on the model to obtain corresponding electric field mode distribution and effective refractive index, and calculating the effective refractive index and absorption coefficient change of the waveguide; constructing a traveling wave electrode model, simulating the traveling wave electrode model to solve an S parameter of a traveling wave electrode, and determining a distribution parameter of the no-load traveling wave microstrip line; a load traveling wave transmission line model is constructed in combination with PN junction electrical characteristic parameters, and based on the model, the frequency response characteristics and the modulation bandwidth of the electro-optical modulator at different temperatures are determined, so that the accuracy of a simulation result can be improved.

A dynamically tunable optical mirror named as a resonant cavity switching (RCS) device and a refractive index modulating (RIM) device are disclosed. The RCS device is comprising a nanoporous piezoelectric III-nitride material layer, such as GaN, AlN, AlScN, AlGaScN or their alloys sandwiched between a high-reflectivity distributed Bragg reflector (DBR) and a lower-reflectivity output DBR. The RIM devise is comprising the nanoporous III-nitride material layer. The nanoporous layer, patterned with interdigital transducers (IDTs), is actuated via surface acoustic waves (SAWs) or electric fields to induce rapid, reversible modulation of its effective refractive index. This enables sub-nanosecond switching between resonant and off-resonant optical states, facilitating efficient energy extraction, optical pulse carving, or phase control.

To provide an onium salt used for a chemically amplified resist composition excellent in solvent solubility, having high sensitivity and high contrast, and excellent in lithography performance such as LWR, CDU, MEF, EL and DOF in photolithography using high energy rays, a chemically amplified resist composition containing the onium salt, and a pattern forming method using the chemically amplified resist composition.SOLUTION: An onium salt having the formula (1): SELECTED DRAWING: None

The application provides a wavelength division multiplexer and a silicon optical chip, which comprises a first unit and at least one second unit; the first unit is connected with each second unit through a first waveguide; an output port and a plurality of output ports are arranged on the same side of the first unit; the first unit and the plurality of second units are each provided with a wavelength interleaver; the wavelength interleaver comprises a homogeneous waveguide and a heterogeneous waveguide; the heterogeneous waveguide comprises a main body composed of a first material; a gap is arranged in the main body; the gap is filled with a second material; along the propagation direction of input light, the wavelength interleaver is provided with an input section, an input coupling section, a phase difference accumulation section, an output coupling section and an output section; the effective refractive index of the homogeneous waveguide and the effective refractive index of the heterogeneous waveguide in the phase difference accumulation section are different. The wavelength division multiplexer can be applied to the manufacture of optoelectronic devices, such as a silicon optical chip. The first unit and the second unit are in a folded layout, so that the layout of the wavelength division multiplexer on the chip is compact and modular.

The invention relates to a mode field separation high-polarization semiconductor laser and application thereof, and aims to solve the problem of low polarization degree caused by stress of an existing laser. The laser comprises a main mode field region and a coupling region which are stacked along an epitaxial growth direction. The main mode field region is used for limiting and lasing a first polarization optical mode; the coupling region is made of a high-loss material and is used for absorbing and attenuating the second polarization optical mode. The two meet the following matching conditions: the effective refractive index of the second polarization optical mode of the coupling region is matched with the effective refractive index of the specific m-order second polarization optical mode of the main mode field region, so that the second polarization optical mode is optically coupled and expanded to the coupling region to be dissipated; the effective refractive index of the first polarization optical mode of the coupling region is mismatched with the effective refractive index of the specific m-order first polarization optical mode of the main mode field region, so that the coupling region is limited in the main mode field region for stable lasing. According to the invention, a polarization-related mode filtering mechanism is utilized, so that the polarization degree and the process robustness of the laser are remarkably improved.

A semiconductor light-emitting structure includes a semiconductor substrate layer, a first limiting layer, a first waveguide layer, an active layer, a second waveguide layer, and a second limiting layer stacked in sequence. The active layer comprises a first superlattice active layer and a second superlattice active layer stacked in sequence, and the second superlattice active layer is located on a side of the first superlattice active layer away from the first waveguide layer. The semiconductor light-emitting structure further includes an insertion layer disposed between the second superlattice active layer and the first superlattice active layer. A refractive index of the insertion layer is less than an effective refractive index of the first superlattice active layer and less than an effective refractive index of the second superlattice active layer.

The invention discloses an infrared super lens with a moth eye imitating anti-reflection nano structure. The moth-eye anti-reflection metasurface, the metasurface lens and the substrate are all made of silicon materials, and the moth-eye anti-reflection metasurface and the metasurface lens are micro-nano-scale arrays and are located on the two sides of the same substrate respectively. According to the invention, the metasurface is fully utilized to finely and efficiently modulate the phase, amplitude and other characteristics of light waves, the moth-eye metasurface changes the effective refractive index of the surface and reduces the reflectivity of incident light on the silicon surface, the metasurface lens enables the phase distribution to meet the spherical wavefront contour, efficient focusing of emergent beams is realized, and the light quality is improved. All micro-nano structures have the advantage of good thermal stability based on the same substrate material, and anti-reflection and focusing effects are achieved in an extremely thin scale.

The invention discloses a dual-wavelength frequency doubling regulation and control method based on a PPLN waveguide, and relates to the technical field of nonlinear optics. The method comprises the following steps: constructing a PPLN waveguide model, and determining a fundamental frequency light mode and a frequency doubling light mode; calculating effective refractive indexes of the fundamental frequency light and the frequency doubling light at respective wavelengths; the polarization period is calculated according to the effective refractive index, any target polarization period is fixed, the target polarization period is configured to correspond to two different working wavelengths at the same time, and therefore dual-wavelength frequency doubling light with a specific wave crest interval is generated at the output end of the waveguide; the wave crest interval is regulated and controlled by selecting different polarization periods; according to the invention, dynamic control of dual-wavelength frequency multiplication output is realized by changing the size of a polarization period; the single waveguide can complete various optical function design ideas, and has certain value for research in related fields such as multi-wavelength lasers and wavelength multiplexing communication.

The application discloses a kind of bound state thin film lithium niobate optical filter based on quasi continuum body.The optical filter is sequentially stacked from top to bottom by tunable filter layer, thin film lithium niobate flat plate, dielectric buried oxygen layer and substrate layer, heating electrode and reflective grating are distributed on both sides of waveguide, periodically arranged reflective grating is arranged between heating electrode and waveguide, the width of waveguide is set to realize bound state in continuum, reduce the lateral leakage loss caused by mode leakage, reflective grating is used to reflect the mode leaked into lithium niobate flat plate back to waveguide to further realize bound state in quasi continuum, heating electrode is used to change the effective refractive index of reflective grating.The application is easy to process, has large tolerance, low loss, and can effectively realize low-loss, narrow-bandwidth photonic filtering, by changing the voltage loaded on the heating electrode to control the center wavelength of the filter without changing the physical structure, filters with different reflection center wavelengths can be realized.

This application provides a resonant modulator applicable to the field of optoelectronic information technology. The resonant modulator includes a substrate layer, a buried layer, a core layer, and an upper cladding layer. The core layer includes a multimode interference coupler and a connecting waveguide. The multimode interference coupler includes a multimode interference region and a main input port waveguide, a main output port waveguide, a feedback output port waveguide, and a feedback input port waveguide. The two ends of the connecting waveguide are optically connected to the feedback output port waveguide and the feedback input port waveguide, forming an optical feedback loop with the multimode interference coupler. An electro-optic modulation unit is associated with a first region of the connecting waveguide and is used to adjust the effective refractive index of the connecting waveguide by applying an electrical signal to change the resonant state of the resonant modulator. Based on the above structure, the sensitivity to coupling spacing and manufacturing errors can be reduced, and the device operating tolerance and modulation stability can be improved. This application also provides an optical computing system and a photonic integrated system.

The invention relates to the field of optical fibers, in particular to a D-type optical fiber based on Fe3GaTe2 nanosheets and a preparation method and application of the D-type optical fiber. The invention discloses a D-type optical fiber based on a Fe3GaTe2 nanosheet. The D-type optical fiber comprises a D-type optical fiber and a Fe3GaTe2 layer deposited on a D-type plane of the D-type optical fiber. By utilizing the evanescent field characteristic of the D-type optical fiber, the Fe3GaTe2 nanosheet is deposited on the D-type plane of the D-type optical fiber, and magnetic anisotropy change (such as magnetization direction switching) is generated under the action of an external magnetic field, so that the effective refractive index of the optical fiber is changed; the change is converted into an optical path difference in the Michelson interferometer. Finally, the magnetic field intensity can be inverted by measuring the FSR change of the interference spectrum. The room-temperature MA adjustability of the Fe3GaTe2 nanosheets provides a larger refractive index change range (superior to that of magnetic fluid), and the nanosheets are not easy to degrade, so that the D-type optical fiber has higher sensitivity and temperature performance.

Disclosed are apparatuses for optical coupling and a system for communication. In one embodiment, an apparatus for optical coupling having an optical coupling region is disclosed. The apparatus for optical coupling includes a substrate and a core layer disposed on the substrate. The core layer includes a plurality of holes located in the optical coupling region. An effective refractive index of the core layer gradually decrease from a first end of the optical coupling region to a second end of the optical coupling region.

A vertical cavity surface emitter (VCSEL) has a body comprising a vertical stack of stacked semiconductor layers, including: a current-limiting region enclosing a low-resistance current-flow region defined by a high-resistance current-flow region, and a first epitaxial sublayer located near the current-limiting region, wherein the first epitaxial sublayer includes a projection or recess defining a main cavity, and the remainder of the first epitaxial sublayer defines an outer cavity;wherein the projection or recess is defined by a physical step h which is predetermined according to the following equation: qλ0 - mλ1 = n0 h where λ0 is a resonant wavelength of the light in the main cavity, λ1 is a resonant wavelength of the light in the outer cavity, q is a positive half-integer, n0 is the effective refractive index in the main cavity, and m is a constant.;

The invention relates to the technical field of multimode interference, and provides a central wavelength tunable multimode interference device which comprises an input waveguide region, a multimode interference region and an output waveguide region which are connected in sequence, the multimode interference region comprises a core layer, the core layer is made of a high-refractive-index material, and the output waveguide region is made of a high-refractive-index material. And a modulation electrode structure for modulating the refractive index of the core layer is arranged on the multimode interference region. The invention further provides a manufacturing method of the multimode interference device with the tunable central wavelength and a coherent modulator. Refractive index modulation is carried out on the core layer of the multi-mode interference area through the modulation electrode structure, in the multi-mode interference area, the effective refractive index directly determines the self-mapping point positions of different wavelengths, therefore, the effect of tunable central wavelength can be achieved through refractive index modulation, and through selection of different bias voltages, the tunable wavelength of the multi-mode interference area can be achieved. And the output effect of the optical power in the output waveguide is tuned.

An electrically switchable liquid crystal cell (10) is provided together with a lens (50) having this liquid crystal cell, and a method for manufacturing the liquid crystal cell. The liquid crystal cell (10) has a diffractive optical element (12) and a liquid crystal material (14) that can be switched between a mismatched (unswitched) state and a matched (switched) state. In the mismatched state, the effective refractive index of the liquid crystal material (14) is different from the effective refractive index of the substrate (18) of the diffractive optical element (12). In the matched state, the effective refractive index of the liquid crystal material (14) matches the effective refractive index of the substrate (18). In the matched state, the diffractive optical element does not contribute to the focal power of the lens. The diffractive optical element (12) has a number of peaks (20) and valleys (30) with rounded corners.

This invention relates to the field of optical waveguide technology, specifically providing a method for driving a liquid crystal waveguide beam scanner. The method involves calculating the director of liquid crystal molecules under an applied electric field, calculating the dielectric tensor based on the director, obtaining the effective refractive index of the optical waveguide based on the dielectric tensor, calculating the scanning angle under different applied electric fields, establishing the dynamic relationship between the scanning angle and voltage, and designing a driving voltage waveform accordingly to achieve a preset beam scanning process. This invention enables precise and predictable beam scanning, fulfilling specific application requirements.

The invention discloses a multi-channel low-crosstalk multi-layer stepped annular optical fiber and a design method thereof, and belongs to the field of optical communication, and the multi-layer stepped annular optical fiber comprises n (n is greater than or equal to 5 and less than or equal to 10) nested annular structure layers which are sequentially the first to nth annular structure layers from inside to outside; the refractive index of the outermost annular structure layer is smaller than or equal to that of silicon dioxide; the refractive indexes of the first to (n-3) th annular structure layers are greater than the refractive index of the outermost annular structure layer; the refractive index of the (n-2) th embedded structure layer is equal to that of the outermost annular structure layer; the refractive index of the (n-1) th annular structure layer is smaller than that of the outermost annular structure layer; the refractive indexes of the adjacent annular structure layers are different; the width range of the first annular structure layer to the (n-1) th annular structure layer is 1-6 [mu] m and is smaller than the width of the outermost annular structure layer. The number of orbital angular momentum modes which can be supported by the optical fiber and are good in effective refractive index separation can be increased, and therefore the optical communication capacity is improved.

A Vertical Cavity Surface-Emitting Laser (VCSEL) has a body comprising a vertical stack of semiconductor layers one on top of the other, including: a current confinement region including an area of low resistance to current flow defined by an area of high resistance to current flow, and a first epitaxial sublayer disposed proximate to the current confinement region, the first epitaxial sublayer including a protrusion or a recess defines a main cavity, and the balance of the first epitaxial sublayer defines an outer cavity; wherein the protrusion or recess is defined by a physical step h that is predetermined according to the equation: qλ0−mλ1=n0h where λ0 is resonant wavelength of light in the main cavity, λ1 is resonant wavelength of light in the outer cavity, q is a half-integer positive number, n0 is effective refractive index in the main cavity, and m is a constant.

The application relates to a three-component distributed optical fiber acoustic sensing device, system and detection method based on microstructure air hole sound wave sensitization, which comprises a distributed optical fiber acoustic sensing system and a sensing device, the device comprises at least one sensing unit, the sensing unit comprises an elastomer and a sensing optical fiber with air holes, and the sensing units are connected by connecting blocks; at least one sensing optical fiber is tightly attached to the elastomer to detect the deformation of the elastomer, and the cladding of the sensing optical fiber comprises air holes; the sensing device is connected with the distributed optical fiber acoustic sensing system. By adopting the microstructure air hole optical fiber as the sensing optical fiber, the equivalent Young's modulus and the effective refractive index of the sensing optical fiber are reduced, the bending loss is lower under the condition of ensuring that the optical fiber attenuation is lower, and the sound wave detection sensitization is realized.

Disclosed are apparatuses for optical coupling and a system for communication. In one embodiment, an apparatus for optical coupling having an optical coupling region is disclosed. The apparatus for optical coupling includes a substrate and a core layer disposed on the substrate. The core layer includes a plurality of holes located in the optical coupling region. An effective refractive index of the core layer gradually decrease from a first end of the optical coupling region to a second end of the optical coupling region.

A multicore optical fiber is provided including a first core region having a first refractive index profile, a second core region having a second refractive index profile, wherein the first core region is separated from the second core region by a separation distance in a range of 20-50 μm, and an outer cladding surrounding the first and second core regions, wherein the first core region exhibits a first effective index and a first group index and the second core region exhibits a second effective index and a second group index, and the first and second effective indices are substantially different to suppress crosstalk and the first and second group indices are substantially the same to achieve a substantially similar group velocity.

A non-degenerate mode few-mode multiplexer / demultiplexer based on a four-core transmission main channel is characterized in that a transmission channel of the mode division multiplexer / demultiplexer is composed of an elliptical four-core super-mode fiber core FEC-SFC and three single-mode fiber cores, the elliptical four-core super-mode fiber core at the coordinate center serves as the transmission main channel, and the single-mode fiber cores SMF1, SMF2 and SMF3 are transmission coupling channels; the length of the transmission main channel FEC-SFC is 3.588 mm, and the lengths of the SMF1, the SMF2 and the SMF3 are respectively 3.588 mm, 1.658 mm and 1.808 mm; the mode field characteristics in the optical fiber can be changed by reasonably setting parameters such as the position, the size and the refractive index distribution of the fiber core; according to the ultra-mode fiber core, the advantages of a pure silicon dioxide fiber core, an elliptical core and an ultra-mode fiber core are fused, the mode degeneracy of LP11a / LP11b is broken, four ultra-mode multiplexing and demultiplexing of LP01, LP11a, LP11b and LP21b are achieved, the refractive index fiber core made of pure silicon dioxide is adopted, and the low-loss performance is achieved; a transmission channel with a large effective refractive index difference is adopted, and the position and the length of the transmission channel are reasonably set, so that the low-crosstalk and high-extinction-ratio performance is realized, and the low-crosstalk and high-extinction-ratio optical fiber can be used for MIMO-FREE operation.

We disclose a liquid crystal lens with a simple structure and high utilization efficiency of the liquid crystal layer. [Solution] A liquid crystal lens comprising a liquid crystal layer in which liquid crystal molecules are oriented and housed between a first substrate having transparent electrodes and a second substrate 12 having transparent electrodes, wherein the transparent electrodes on the surface of the second substrate consist of a plurality of concentric annular electrode groups 231 to 239 connected in series and a central electrode 230, and the liquid crystal lens adjusts the distribution of the effective refractive index of the liquid crystal layer by applying a voltage having an axially symmetric potential distribution to the liquid crystal layer, wherein the liquid crystal lens operates by applying a voltage different from the voltage that forms an axially symmetric potential distribution to at least one electrode of the concentric annular electrode group.

The invention relates to the technical field of optical waveguides, and particularly discloses a manufacturing method of an optical waveguide end face coupler and the optical waveguide end face coupler, in the process of manufacturing the optical waveguide end face coupler, a dielectric material, namely silicon oxynitride or silicon oxycarbide, is deposited on a siliceous substrate wafer through a CVD method in a CMOS process, in the manufacturing process, the manufacturing process can be connected with the manufacturing process of an electronic device, the high-refractive-index gradient layers of the lower gradient layer, the middle gradient layer and the upper gradient layer and the core layer are finally manufactured, and the effective refractive index is linearly changed in cooperation with a common insulating medium in the semiconductor technology, namely, the low-refractive-index gradient layers prepared from silicon dioxide, and the effective refractive index is changed in a linear mode. And based on the characteristic that the refractive indexes of the silicon oxynitride and the silicon oxycarbide are adjustable, the optical waveguide end face coupler which can adapt to a semiconductor photon-electron heterogeneous integrated scene, can be compatible to the manufacturing process of an electronic device and has a wide-range core cladding refractive index difference is finally obtained.

The invention relates to a flexible design method of refractive index constraint in an overgrowth-based vertical cavity surface emitting laser. A vertical cavity surface emitting laser (VCSEL) has a body including a vertical stack of semiconductor layers one above the other, including a current confinement region including a region of low resistance to current flow defined by a region of high resistance to current flow, and a first epitaxial sub-layer disposed proximate to the current confinement region, comprising protrusions or depressions defines a main cavity, and the remainder of the first epitaxial sub-layer defines an outer cavity; wherein the protrusions or recesses are defined by a physical step h predetermined according to the following formula: q [lambda] 0-m [lambda] 1 = n0h, where [lambda] 0 is the resonant wavelength of light in the main cavity, [lambda] 1 is the resonant wavelength of light in the outer cavity, q is a positive half integer, n0 is the effective refractive index in the main cavity, and m is a constant.

The invention discloses an optical phased array transmitting system based on end face emergence. The optical phased array transmitting system comprises an antenna array composed of tip Si waveguides and a concave reflector based on a liquid crystal spatial light modulator. An SOI substrate in the antenna array comprises a substrate silicon layer and a buried oxide layer, a Si waveguide layer is located above the buried oxide layer and used for transmitting a light field, and the upper layer is covered with SiO2; similar cylindrical Fresnel lens phase distribution is applied to the LCOS-SLM liquid crystal spatial light modulator, so that the condensation performance similar to that of a cylindrical concave reflector is formed, and the longitudinal divergence angle of an emergent beam is reduced. Tip processing is carried out on the tail end of the Si waveguide, the emission efficiency is improved by introducing gradual change of the effective refractive index, meanwhile, an end face emission optical phased array antenna array is formed, the transverse light beam scanning capacity is achieved, deflection of different degrees is generated based on the main optical axis of the concave reflector, the longitudinal angle of reflected light is changed, and the reflection efficiency is improved. Therefore, the longitudinal scanning of the light beam is realized.