This PDF file contains the front matter associated with SPIE Proceedings Volume XXXXX, including the Title Page, Copyright information, Table of Contents, and Conference Committee information.

T-rail electrodes has emerged as a promising candidate for increasing the electro-optical modulator(EOM) bandwidth, compared to traditional travelling wave electrodes. We demonstrate an equivalent model of thin film lithium niobate (TFLN) Mach-Zehnder modulators with T-rail electrodes, utilizing the distributed capacitance and conformal mapping techniques to calculate the microwave refractive index, RF characteristic impedance, microwave loss. The validity of the values extracted from the equivalent circuit model is confirmed by their agreement with finite element method (FEM) simulations. We analyze various influential parameters affecting modulator performance to enhance design efficiency and achieve a 3dB bandwidth of approximately 120 GHz.

A three-section dual-transverse mode hybrid resonant laser has been successfully developed on the InP platform, utilizing a 2D sampling grating. This laser comprises an active section with a π phase-shifted anti-symmetric Bragg grating (π-ASBG) and two passive sections with uniform Bragg gratings (UBGs). With this design, it enables the simultaneous and stable emission of both the fundamental transverse electric mode (TE0) and the first-order transverse electric mode (TE1). The physical mechanism of dual-transverse mode hybrid resonance in the cavity of a semiconductor laser is analyzed, based on the coupled-mode theory. The experimental results indicate that the laser consistently maintains an output wavelength of 1549 nm, achieving side-mode suppression ratios (SMSR) of 38 dBand30 dB, respectively, under the emission of the TE0 mode and the TE1 mode. Therefore, as the transverse mode tunable light source, the laser may benefit the future mode division multiplexing (MDM) systems for more reconfigurability and flexibility.

A digital-SiPM based dTOF sensor with PDP optimization is proposed in this paper. The dTOF sensor consists of a configurable charge pump and a digital-SiPM including a 4×4 SPAD array. Exploiting a configurable charge pump, the bias voltage across the SPAD can be adjusted according to the background light intensity, hence optimizing the photon detection probability (PDP). The proposed dTOF sensor is designed in 110nm CIS process, with an active area of 555 μm × 638 μm. The post-layout simulation shows that the bias voltage can be adjusted from 16V to 20V. The maximum voltage drop caused by the avalanche current is 68 mV with all SPADs triggered simultaneous under various PVT conditions, and the 99 % recovery time for the output voltage is about 20 ns.

The current stage of research on the integration of optical fire and smoke detection sensor technology, the current basic focus on red and blue dual-wavelength fire and smoke sensors and the rest of the fire detection information integration technology, specifically for the three-wavelength optical circuit simulation design and integration of the research is less; for the multi-wavelength optical black and white smoke detection balanced technology design of the research is also very little. In view of the above problems, this paper designs a three-wavelength smoke detector based on STM32 microcontroller on the basis of ADPD188BI sensor. This thesis uses embedded technology, based on the ADPD188BI dual-wavelength integrated optical module sensor, in order to carry out technical combing of hardware and software design focus, complete the circuit integration design, to achieve the sensor hardware and software integration design, and in accordance with the national standards GB 4715-2005 "point-type smoke-sensing fire detector", GB20517-2006 "standalone smoke-sensing fire detection Alarm" and other standards independently developed, designed and manufactured test smoke box to carry out compliance with the national standard GB 4715-2005 "point-type smoke detector" performance test verification.

We present a waveguide-integrated electro-absorption modulator utilizing GeSi alloy technology with a butt-coupling configuration. By introducing a poly-Si taper, the coupling efficiency of the modulator is maintained above 95% within the 1500-1600 nm wavelength range. The demonstrated device achieves a 3dB bandwidth of up to 197 GHz at the wavelength of 1550 nm, an extinction ratio of 5.32 dB, and an insertion loss of 2.68 dB. Additionally, the modulator exhibits excellent detection performance with a responsivity of 0.986 A/W.

A novel high-power charge-compensated modified uni-traveling carrier (CC-MUTC) PD on a semi-insulating InP substrate was designed and fabricated. To extend its 3-dB bandwidth, its absorption layer adopted a p-type Gaussian doping structure, and thickness of the InP substrate is reduced to 12µm. The back-illuminated device was flip-chipped mounted on a 100µm-thick diamond-based coplanar waveguide circuit to facilitate heat dissipation. Typical responsivity of the fabricated PDs is 0.7A/W at 1.55μm wavelength for a bias voltage of -6V. The output power of 20.4dBm was measured at 8GHz, 21.7dBm at 10GHz and 19.4dBm at 12GHz. The newly designed UTC-PD has sufficiently good potential for application in need of the high output power and also for next-generation digital and analog optical fiber transmission systems.

We propose and experimentally demonstrate a scalable programmable silicon photonic processor for solving differential equations. This processor is composed of an array of ellipital microrings (MRRs) and 16-channels of tunable delaylines. The MRRs is cascaded to offer flat-top filtering response to select/combine/amplitude control the carrier wavelength of the input optical signal. The following sixteen-channel delaylines are realized by 7-bit ultra-low-loss broadened waveguides and low-phase-error Mach-Zehnder interferometer for 0~330.2 ps time-delay with a step of 2.6 ps. By using wavelength division multiplexing and amplitude/phase control techniques, the processor enables parallel signal processing in each channel, offering scalability and programming flexibility. By programming the silicon photonic processor, a reconfigurable intensity differentiator with variable differentiation orders can be achieved. The operation principle is theoretically analyzed and this programmable silicon photonic processor has been demonstrated successfully to verify the first-, second- and third-order intensity differentiator functionality, which can be used in the field of optical computing.

We design a type of broadband Silicon Nitride (SiN) power splitters with various split ratios using shortcuts to adiabaticity (STA) technique to ensure the compactness and performance of the device. The decoupled system states are employed in the double-waveguides system to guarantee the approximate adiabatic evolution and the desired split ratios are implemented by manipulating the boundary conditions. The devices show broadband response for a wide wavelength range from 1260 to 1360 nm and have excellent robustness against fabrication errors in our simulations.

Nowadays, the Von Neumann computing structure, which separates storage and computation, limits the rate of data processing. There is an urgent need to design chips with integrated storage and computation functions to avoid the problem of data transportation fundamentally and reduce the time needed for transmission. Inspired by the integration of neurons and synapses in the human brain with storage and computation, people began to study brain-like chips. Synapse simulation is the key to the manufacture of brain-like chips, in which photoelectric synapses have the advantages of low crosstalk, large bandwidth, low latency and low power consumption, but also simulate human vision, which has become a hot spot of synapse research. In this thesis, photoelectrical synaptic devices with the structures of ITO/BST:Ag/SiO₂/P-Si/ITO were fabricated by magnetron sputtering method. The synaptic performance and the working principle of the device was investigated. Finally, this article randomly selects 25 ITO/BST: Ag/SiO₂/P-Si/ITO synaptic devices to form a 5 × 5 array, ensuring that each unit device is isolated from each other and the current is not affected. Use light pulses with different parameters to excite each unit device, record the current value of the device, simulating the image memory function of the human eye.

This paper presents a high-directionality optical grating antenna for chip-level LiDAR applications. The antenna, designed on a silicon-nitride-nitride platform, consists of two vertically stacked grating layers with a nitride waveguide layer in between. By optimizing the grating periods, duty cycles, and the relative offset between the grating layers using a particle swarm optimization algorithm, a directionality of 87.8% (0.56 dB) at 1550 nm wavelength and a minimum coupling loss of 1.7 dB were achieved. The performance of the antenna was demonstrated in a chip-to-chip transceiver configuration using a coherent detection system. With a transmitter output power of 10 dBm, the system achieved a signal-to-noise ratio of 17.7 dB and 13.2 dB at screen distances of 20 m and 40 m, respectively. These results highlight the potential of the proposed antenna for long-range, chip-level LiDAR applications.

Currently, integrated optoelectronic technology has made significant progress in commercial applications. However, existing technologies are approaching their theoretical limits. How to introduce new materials to achieve novel on-chip optical field control and generate disruptive breakthroughs will be crucial for meeting the future demands of optical computing, optical communication, optical sensing, and other applications. Chalcogenide materials, also known as chalcogenide glass materials, mainly refer to compounds containing sulfur, selenium, tellurium, and other chalcogen elements. They not only possess excellent nonlinear optical properties and excellent micro-nano processing characteristics but also some specific compositions of chalcogenide glass exhibit nonvolatile phase transition characteristics for exploring nonvolatile reconfigurable photon platforms. This paper will mainly introduce some progress in our research on scalable fabrication techniques for integrated photonic devices based on chalcogenide materials.

Traditional electronic computing methods are hitting their limits as data processing demands continue to escalate. Optical neural networks (ONNs) present a promising solution to overcome this challenge. The microring resonator (MRR) weight bank (WB), which provides distinct weights for various light wavelengths in optical neural networks (ONNs), is advantageous due to its compact size, scalability, ease of tuning, and natural compatibility with wavelength division multiplexing (WDM). Despite these benefits, MRRs are highly sensitive and experience uneven transmission power with wavelength shifts, leading to inefficient and imprecise tuning. In this work, we successfully demonstrate a dual-drop microring weight bank (DDMRR-WB) with linear configuration, maintaining weight precision over 4.3 bits.

Fiber Bragg grating (FBG) extensively employed in a variety of ways. In this paper, we designed an FBG sensor structure and introduced a novel method to determine the angle of vibration source. The performance of our sensor and the method were validated through experiments. We placed the sensor in a controlled water tank environment, utilizing a spherical object to generate vibration as the vibration source to stimulate the sensor. Through the FBG wavelength shifting data, the angle of ball was determined by the method. The results showed that the average deviation was only3 degrees, with an accuracy rate of 90%. Our finding demonstrate that this novel sensor has a better perception capability for minor vibrations and the angle determination method for the vibrating object has excellent accuracy.

We present a high-efficiency silicon optical switch utilizing a silicon-GSST hybrid integrated waveguide. Optical wave propagating in the hybrid waveguide is modulated through the phase change of GSST. This phase change is triggered by electro-thermal heating from a PIN diode located beneath the GSST strip. We employ the hybrid integrated waveguide as a phase shifter and incorporate a Mach-Zehnder Interferometer (MZI) structure to serve as an optical switch. The device supports over 1000 effective switching events. Additionally, multi-level switching is achieved on a single waveguide, offering 128 non-volatile transmission levels. Our research indicates significant potential applications in optical switching, computing, and storage.

The Low-light image sensor is the photoelectric detector for imaging in the environment of full month illumination and lower illumination. The main detector types include the electrical gain detector represented by EMCCD, the optical gain detector represented by MCP detector, and the latest scientific CMOS image sensor (sCMOS). EMCCD uses high voltage electric field to multiply electrons after photoelectric conversion, so as to improve photoelectric conversion sensitivity. MCP uses high voltage electric field to multiply electrons converted by photo-cathode materials, which improves the photon flux of dim targets, and thus improves the sensitivity of detector to dim targets in low light environment. Scientific CMOS image sensor is proposed in recent years that does not rely on external structure, and obtains high sensitivity by optimizing CMOS pixel technology, pixel structure and readout circuit noise level. Based on the optical and electrical parameters of the these kinds of low light level detectors, this paper analyzes the calculation methods of SNR of the these kinds of low light level detectors in detail, and expounds the theoretical characteristics and application fields of the these kinds of low light level detectors.

Integrated optical 90-degree hybrid has the advantages of compact structure and stable performance, which has been implemented on different integrated platforms, including silicon-on-insulator, silicon nitride, InP, and so on. InP is a promising platform for photonic integrated circuits (PIC) with both passive and active devices. Here, we simulated, fabricated, and demonstrated an InP optical 90-degree hybrid using a 4×4 multimode interference coupler. The designed device exhibits a phase error within ±5° in a spectral range from 1540 nm to 1565 nm, a common mode rejection ratio better than 19.6 dB, and an imbalance less than 0.91 dB in a spectral range from 1545 nm to 1560 nm experimentally. Performance improvement is on the way by optimizing the fabrication process.

Silicon nitride-on-SOI grating couplers are specifically designed for the O- and C-bands, utilizing CUMEC's advanced process platform. Through simulation, we have achieved an impressive maximum coupling efficiency of -1.4 dB and -1.8 dB to standard single-mode fiber for the O- and C-bands respectively, accompanied by a remarkable 1-dB bandwidth of 70 nm and 78 nm. Furthermore, we have conducted an analysis on fabrication variation tolerance.

Optical circulators enable bidirectional transmission of light and play an important role in data centers, communication networks and LIDAR. The integration of optical circulators is currently one of the thorny issues limiting the full integration of optical systems, and the usual schemes require hybrid integration of magneto-optical materials to break the optical reciprocity. In this work, we propose a thin-film lithium niobate (TFLN) optical circulator consisting of a traveling-wave electrode modulator (TWEM) and micro-ring resonators (MRRs). It realizes optical non-reciprocity based on the phase accumulation asymmetry of forward and backward traveling wave modulation, and adjusts the path of light with the help of the MRRs. The circulator has four optical channels to realize the light propagation along the 1-2-3-4-1 spatial sequence. The calculated isolation of each channel is greater than 20 dB, and the channel loss is less than 3 dB. Our scheme is wavelength-tunable, scalable, and process-friendly, and provides a promising implementation route for all-optical integration.

Among the various approaches to heterogeneous integration, micro transfer printing (MTP) is a practical and emerging heterogeneous integration method. Typically, the components integrated by MTP are thin-film components and the process of MTP usually requires a sacrificial layer and materials like photo resists as tethers to fix the components. In this work, we demonstrate a tetherless MTP method. We built a complete setup for MTP. We use this setup and a flexible thin-film PDMS stamp with micro-structures as a transfer medium to directly pick up active optical components from a dicing tape with ejector assistance, and then print them directly onto a silicon wafer substrate without any adhesive. And we only require van der Waals force to complete the entire MTP process. Experiments have demonstrated that this method can transfer active optical components of various sizes and thicknesses without contamination and the performance parameters of these components are not affected. The responsivity of avalanche photo diode tested by the manufacturer is 0.9A/W and tested after being transferred at -25V bias is 0.83 A/W. The dark current of the device after being transferred is 13nA at a bias of -13V, which is similar to the value tested by the manufacturer, both at the nanoampere level. We have also attempted to use this new MTP method to transfer an array of semiconductor optical amplifiers, which provides a way to transfer a large number of optical components of various sizes and thicknesses for the practical implications of product packaging and product’s application.

Mach-Zehnder Interferometer (MZI) topological cascade architectures, which allow linear transformations between multiple channels simultaneously, are gradually becoming a powerful tool for photonics and have a place in optical neural networks. This paper focuses on the theoretical analysis and software simulation of two unitary matrix architectures for a 6×6 MZI-based optical processor: the triangular architecture and the rectangular architecture. Both unitary arrays are composed of fifteen reconfigurable MZI units, each of which is comprised of two adjustable phase shifters and two 3-dB directional couplers. For a given neural network training application, the value of each phase shifter can be calculated from the matrix factorization process. The theoretical derivation is verified through simulations using the advanced software Max-Optics. When compared with Lumerical INTERCONNECT, the maximum error is less than 0.00044%, and the simulation time is reduced by 3 times.

This paper presents a comprehensive study on the properties of strain-compensated In_1-x-yGa_xAl_yAs/In_1-x-yGa_xAl_yAs quantum wells matched in InP substrate for 1654nm VCSELs. The physical properties of In_1-x-yGa_xAl_yAs/In_1-x-yGa_xAl_yAs quantum wells are studied. We executed an in-depth study concerning the gain characteristics of different quantum well structures for 1654nm VCSELs, then candidate quantum well combinations are obtained. In addition, the gain-carrier properties of the selected quantum wells are also studied. The results show that the quantum well structure, In_0.749Ga_0.205Al_0.046As/In_0.42Ga_0.43Al_0.15As quantum well of 6nm, is more suitable for 1654nm VCSELs due to its properties: larger band-gap offset, higher material gain, low transparency carrier density and higher differential gain. The VCSELs with it would have better photoelectric properties. This study provides valuable insights for optimizing active region of VCSELs suitable for 1654nm methane detection and improving device performance.

In view of the characteristics of the target product, such as diverse feature data types, huge capacity, and large number of unstructured and semi-structured data, based on the domestic autonomous controllable platform, we adopt the hybrid storage architecture of massive feature data files combining relational database and Hadoop, and use relational database to store structured feature data. The Hadoop cluster is used to store semi-/ unstructured data, make up for the shortcomings of relational databases in mass data processing and storage, and achieve high concurrent access to big data of target products and scalability of heterogeneous data.

Integrated sources of indistinguishable photons have garnered significant attention due to their applications in optical quantum computing, quantum communication and quantum networks. However, photons generated from spontaneous four-wave mixing (SFWM) always occur in pairs, which need to be split into different modes for further applications. Here, we present a quantum splitter for degenerate photon pairs based on a silicon photonic chip. This device incorporates a Sagnac loop, two asymmetrical Mach-Zehnder interferometers (AMZIs), and a spiral waveguide. The spiral waveguide generates pairs of photons, the Sagnac loop facilitates bidirectional pumping of the source, and the two AMZIs enables the extraction of photons from the pump light. The photons generated from two directions interfere at a balanced multi-mode interferemeter (MMI) to enable the reversed Hong-Ou-Mandel (HOM) effect to take place. Our experimental results demonstrated an on-chip interference visibility of 96.63% and an off-chip HOM dip visibility of 90.93%, indicating that the generated photons are well-suited for further integration with other components in quantum applications.

Lidar is one of the core sensors in autonomous driving vehicles. However, the mass production testing of automotive lidars currently faces challenges in terms of large space occupation and long time cost. To overcome these limitations, we develop a test instrument called lidar scene projector (LSP) to realize efficient testing and small space requirement. The LSP captures the laser pulses transmitted by the lidar within a large field of view (FOV) and generates laser return signals carrying distance, intensity, and direction information. The laser return signals are then projected to the lidar under test through a tracking scanning module to ensure real-time direction matching between the laser return signals and the lidar transmitted laser pulses. The LSP covers a FOV of 15°(horizontal) × 30°(vertical) and only occupies a space less than 1.5m×1.5m×0.5m. It can easily change the simulation distance and return signal intensity via PC. The LSP can serve as a terminal test instrument on the mass production line of automotive lidars to significantly enhance the testing efficiency.

A novel inverse design algorithm based on intelligent searching and greedy threshold mechanism is proposed. Compared with the traditional adjoint algorithm, this method does not have the binarization-induced deterioration, and is applicable to any optimization problems, even the objective function cannot be written as an analytic expression. Therefore, it has higher efficiency, stronger operability and wider application scenarios. Based on this inverse design algorithm, ultra-compact low-loss 90-degree bending waveguides and high extinction ratio wavelength-division multiplexers are successful demonstrated.

Linear Weighting Method(LWM) and Multi-Objective Particle Swarm Optimization (MOPSO) Method are two popular approaches for addressing multi-objective problems. LWM suffers from strong subjectivity, making it challenging to ensure that each objective is adequately optimized. Meanwhile, MOPSO demands substantial computational resources, is prone to getting trapped in local optima, and its convergence accuracy as well as the uniformity of solution set distribution remain areas for improvement. In the context of inverse design for photonic devices, the problem of dual objectives is particularly prevalent. By employing a two-step inverse design method, we efficiently designed a 50% : 50% directional coupler tailored for operation in the O-band within a relatively short timeframe, requiring only two iterations of a conventional Particle Swarm Optimization algorithm(PSO). This coupler boasts an exceptionally low Insertion Loss(IL) of 0.034dB and a minute Power Splitting Ratio Error (PSRE) of 1.19 × 10⁻⁶. Furthermore, it features a compact footprint of 138um, underscoring its practicality and efficiency.

Heterogenously-integrated semiconductor optical amplifiers (SOA) on the silicon photonics platform have demonstrated advantages such as on-line optical amplification、small figure size and high nonlinearity. While, maintaining high coupling efficiency and large fabrication tolerance at the same time for the coupling between the IIIV optical amplification section and silicon on insulator (SOI) waveguide is still a challenge. Although the edge coupling and abrupt coupling have less alignment accuracy requirements, the total coupling loss is still high due to the mode mismatching. The adiabatic taper structure demonstrates a low coupling loss while the starting width of the active taper is typically down to 100 nm (or even smaller). Especially, it will lead to an unstable mode distribution within the quantum well gain region when it is extended until 1 micron. In this paper, we propose a novel coupling structure involving a slanted active taper structure on top of a smoothly-bending Si waveguide. FDTD/EME simulation results demonstrate that the overall coupling efficiency can be optimized to a level of more than 98% even that the active taper width is up to 1 micron, and the confinement factor in the quantum well can still be stable around 3.8% overall the whole coupling structure. This structure can be beneficial to improve the saturation power of heterogeneous integrated SOA.

Due to the mismatch between the light output of edge-emitting lasers and the optical field mode transmitted by silicon waveguides, as well as differences in material structure and coupling interfaces, primarily due to spot size and shape, prevent effective direct coupling between the laser and waveguide. Additionally, there is an air gap at the coupling interface. The traditional silicon photonic platforms (such as silica-silicon) have a lower contrast in the core/layer refractive index of the waveguide, which limits the actual coupling efficiency between the laser and the waveguide facet to be even lower than the theoretical value. The initial spot diameter of the laser is about 2~3μm, diverging conically with vertical and horizontal divergence angles of approximately 33° and 21° respectively, forming a vertically elliptical spot profile. The cross-section width and height of the silicon optical waveguide are 0.45*0.22μm, with its mode field being horizontally elliptical in shape. Therefore, in order to solve the coupling problem of these two part, this paper designs and studies a trident end-face coupler, achieving efficient direct proximity coupling between the end-face of silicon waveguide and the laser. Common solutions to these problems include: (1) Designing new coupler structures to improve the match between the laser's output light and the silicon waveguide's mode field. (2) Enhancing the alignment accuracy of the coupling platform to ensure the accuracy of the coupling process. (3) Optimizing the laser design to reduce the divergence angle while ensuring better matching with the silicon waveguide with a width and height of 0.45*0.22μm. (4) Reducing air gaps, such as chip end face flatness and roughness, as well as the parallelism between the two coupling ends, to ensure effective fitting between the two coupling ends. These measures can all enhance the coupling efficiency between the laser and the silicon waveguide. This paper designs and studies a trident structure end-face coupler, which directly couples the laser's output end face with the silicon waveguide. The output power of the laser before and after coupling with the silicon waveguide, minus the transmission loss of the waveguide, represents the coupling loss between the laser and the silicon waveguide. The transmission loss is calculated based on the length of the waveguide, which is 0.78dB (waveguide length of 5.20mm, with a transmission loss of 1.50dB/cm). Under experimental conditions of 23°C and 53% relative humidity, the laser was powered within its rated I_op range. The operating wavelength of the laser was 1342nm, with an operating temperature of 45°C. Five sets of valid data were obtained through testing and measurement, showing coupling losses of 3.12dB, 3.05dB, 3.19dB, 3.15dB, and 2.97dB respectively. After subtracting the transmission loss of 0.78dB, the actual losses were 2.34dB, 2.27dB, 2.41dB, 2.37dB, and 2.19dB respectively. Through comparative analysis, it was concluded that compared to the traditional aspheric lens with a coupling efficiency of 35%~45%, i.e., a coupling loss of about 3.5~4.6dB, the current trident facet coupler has a coupling performance superior to the traditional aspheric lens by approximately 1.1~2.4dB. It also avoids the complex process structure of lens coupling, which inevitably introduces additional insertion loss in the coupling optical path. Moreover, the simplified structure is beneficial for improving system stability. At the same time, this structure can also be extended to the research of silicon photonic integrated chips, reducing the complexity of packaging processes and optics structures, and is also conducive to controlling manufacturing costs for industrialization.

Mid-infrared detectors are extensively studied due to their significant applications in aerospace, non-destructive testing, and environmental monitoring. However, currently used mid-infrared detectors require low temperature working conditions, significantly limiting their development. Here, we adopt semimetal ZrTe₃ with zero bandgap characteristic, which enables the effective absorption of mid-infrared electromagnetic waves with low photon energy. The single point detector achieves the responsivity of 0.626 A/W with -0.2 V bias at 4.6 μm. Moreover, we fabricated the 8×1 ZrTe₃ linear array, which achieved the non-uniformity of 7.37% and the noise equivalent temperature difference of 56.9 mK. Our research provides new insights for the development of room-temperature mid-infrared detectors.

Silicon-based integrated spiral waveguides are extensively used as on-chip single-photon sources. However, inherent uncertainties and limitations in single-photon fidelity pose significant theoretical performance bottlenecks. These challenges often necessitate the multiplexing of multiple sources. In this paper, we propose a novel scheme for spatial multiplexing using bidirectional spirals. By pumping a spiral waveguide bidirectionally, photon pairs are generated in both clockwise (cw) and counterclockwise (ccw) directions, each producing signal-idler photon pairs in a two-mode squeezed state. Consequently, a single spiral waveguide can function as two spatially multiplexed sources. Using CMOS fabrication technology, we constructed a bidirectional spiral waveguide structure. We measured the coincidence count rates, heralded second-order correlation function, and coincidence to accidental ratio (CAR) as functions of pump power, both before and after multiplexing. Our experimental results demonstrated a 1.67-fold increase in performance post-multiplexing. This finding underscores the potential of bidirectional spirals as spatially multiplexed sources, paving the way for the largescale integration of future photonic quantum chips.

The rapid advancement in integrated optics offers a viable approach for further reducing the size and weight of interferometric fiber optic gyroscopes (IFOGs) by integrating optoelectronic transceiver modules. This paper proposes a design for an integrated optoelectronic transceiver module for IFOG, incorporating a superluminescent laser diode (SLD) light source, beam splitter, photodetector (PD), and transimpedance amplifier (TIA). Through optimization of the optical path and structural design, the emitted optical power from the fiber pigtail exceeded 1 mW under a 100 mA drive current, with the closed-loop overall loss measured at approximately 13 dB. An integrated IFOG test system was developed, and its zero-bias stability was measured at 0.3755 °/h, meeting the requirements of tactical-grade systems. The transceiver shows substantial potential to streamline the IFOG assembly process and reduce assembly costs, a critical factor in the miniaturization of IFOGs.

We design an elliptical hole waveguide to significantly enhance the optical field localization and confinement in the device. By optimizing the parameters of the proposed device, a flat dispersion region in the communication band is obtained to satisfy the phase matching condition. As a result, the simulated conversion efficiency of the four-wave mixing process is improved by 5.9 dB compared to similar silicon strip waveguide devices.

Ultraviolet single photon detection can be used for real-time capture of faint celestial optical signals in extreme spatial environments. Vacuum-based detectors, due to their good time characteristics, high spatial resolution, and large area reception capabilities, are widely utilized in astronomical observations, space weather monitoring, and sun-blind zone early warning systems. However, challenges such as low spatial resolution exist in current ultraviolet single photon detection systems due to limitations in real-time information acquisition and signal processing. This paper proposes a high-speed digital processing circuit system based on transfer function optimization, digital filtering, and high-precision synchronization. Experimental results demonstrate that signals processed by the circuit exhibit high conversion accuracy, good linearity, and consistent output synchronization. which can increase the signal amplitude collection FWHM to 4.74 and improve imaging accuracy to 78μm on the UV photon counting detector with an effective diameter exceeding Ø40mm. It provides ideas and certain engineering application solutions for the spatial application and optimization of ultraviolet single photon detection.

Optical directed logic circuits aim to perform multifunction logic operations using the optical switch network, in which the digital electrical signals regarded as the logic operands are applied to the optical switch to control the propagation of light over time, and the logic operation results are obtained at the output ports of the optical switch network in the form of light. Full-adder is the primary elementary unit for the realization of optical directed logic which generates both sum and carry bits in optical domain, for three given digital electrical signals. In this letter, we propose an on-chip Microwave Photonic Full-Adder gate for directed logic operation using silicon micro-ring resonators (MRRs). The possibility of using Silicon-on-insulator (SOI) based MRR as thermo-optic switch is described through thermo-optic effect. Three electrical input signals (logic operands) are applied across the micro-heaters above MRRs to determine the switching states of MRRs, and the full-adder logic operation results are directed to the output ports in the form of light, respectively. For proof of concept, the scattering matrix method is employed to establish numerical model of the device. Simulation results confirming described method are presented in this paper.

Si₃N₄ waveguides have been posited as vital photonic devices for next-gen photonic integrated circuits (PICs) due to their excellent properties of broad transparency, low loss, thermal stability, and Complementary Metal Oxide Semiconductor (CMOS) compatibility. In this work, we focused on the simulation design and experimental studies of Si3N4 waveguides based splitters and couplers at 850nm, ensuring the optimized single-mode operation, minimizing dispersion, and highlyefficient transmission of light. A major challenge, inefficient fiber-waveguide coupling, was addressed by developing a special optimized taper waveguide, achieving a theoretical coupling efficiency boost from 11.21% to 99.7%. By meticulously tuning the width and height of the multimode interference (MMI) region to 18.26μm and 4μm, respectively, and positioning the output single-mode waveguides at an optimized distance of 2.05μm, we achieved a remarkable singl-eend transmission of over 49.8%, ensuring balanced and efficient signal distribution crucial for complex networks. The coupling loss of fiber to waveguide was calculated to be as low as 0.013dB compared to that of 9.5dB, and the insertion loss of MMI was calculated to be as low as 0.09dB. In summary, our work realized Si₃N₄-based waveguides for the enhanced coupling efficiency and optimized MMI splitters with excellent performance improvements to form the backbone of more efficient, compact, and high-performance photonic systems, such as the integrated optical gyroscope, on-chip optical sensors, etc.

In this paper, the basic principle of Fano resonance and its application in optical sensors are discussed. On the basis of the theory, a feedback waveguide structure based on silicon nitride (Si3N4) material is proposed. The Fano resonance line can be controlled precisely by changing the related parameters, such as the distance between the micro-ring and the feedback waveguide, the period and the radius of the nanopore. The simulation results demonstrate that the designed device generates sharp Fano resonance peaks in a specific wavelength range, in accordance with the theoretical analysis. The sensitivity of 130 nm/RIU and free spectral range (FSR) up to 54.55 nm, indicated that it is suitable for high-precision chemical and biological analysis. Compared with traditional optical sensors, the device structure based on silicon nitride material exhibits large detection bandwidth, high sensitivity and ultra-low insertion loss. In addition, the footprint of the designed device is 25 × 15 um, which is smaller than conventional microring resonant cavities. With the advantages of the ultra-compact, large detection bandwidth, high sensitivity and low insertion loss, the proposed feedback waveguide can be widely used in biochemical detection, environmental monitoring, food safety and medical diagnosis.

The nonlinear dynamical characteristics of an integrated mutual-injection semiconductor laser (IMSL) with three-section are numerically simulated, and Hopf bifurcation diagrams of its output characteristics varying with different input parameters are presented. The simulation results in this paper indicate that by varying some operating parameters such as coupling strength and detuning frequency of an IMSL, its output exhibits rich nonlinear dynamical behaviors such as injection locking, period-one oscillations, period-two oscillations, multi-period oscillations, quasi-period oscillations, and chaos oscillations. In this paper, we explore the effect of parameter changes of IMSL on its output characteristics, numerically simulate these phenomena and reflect in the Hopf bifurcation diagram.

With the improvement of network rate, whether it is in the access network, transmission network, data center, intelligent computing center, multi-wavelength transmission has been more and more applications, the recent development of optical frequency comb technology has become a hot spot in the industry, a single optical device at the same time to send multi-wavelength signals become possible, with the increase in the number of wavelengths, the wavelength division multiplexing device will produce new demand, At present, WDM devices mainly include TFF thin film filter type and waveguide type. The advantages of TFF thin film filter type WDM are small insertion loss, high isolation, large bandwidth, cheap price and high reliability. The disadvantages are that lens convergence is required and the size is large. The disadvantages of PLC type are high insertion loss, low bandwidth and low isolation, which need to be cascaded to improve isolation. In this paper, a miniaturized and highly density WDM array device is proposed. Combining the advantages of TFF thin film filter and waveguide WDM, we simulate and design a group of Y-type PLC waveguide array, and open a 25um wide slot at the Y waveguide node by means of slice. The ultra-thin TFF film filter of about 20um is inserted into the slot, and the transmitted light and reflected light are derived through the transmitted waveguide and reflected waveguide to realize the WDM function. By optimizing the cone length and width at different Y junction, as well as the cutting position, we obtain that the transmitted path insertion loss is 0.77dB and the reflected path insertion loss is 1.07dB. Compared with traditional thin film filter type WDM, the number of WDM that can be placed on the same size in this scheme is more than 60 times, which greatly improves the space utilization rate, and simultaneously combines the advantages of TFF type WDM and waveguide type WDM. Subsequently, by improving the coupling accuracy, reducing the roughness of grooves or using etching method to make TFF slot, The insertion loss can be further reduced.