Tunable narrow band add-drop filter design based on apodized long period waveguide grating assisted co-directional coupler

A Comprehensive Exploration of Contemporary Photonic Devices in Space Exploration: A Review

Photonics plays a pivotal role in propelling space exploration forward, providing innovative solutions to address the challenges presented by the unforgiving and expansive realm of outer space. Photonic-based devices, encompassing technologies such as lasers, optical fibers, and photodetectors, are instrumental in various aspects of space missions. A notable application is in communication systems, where optical communication facilitates high-speed data transfer, ensuring efficient transmission of information across vast interplanetary distances. This comprehensive review unveils a selection of the most extensively employed photonic devices within the realm of space exploration.

Towards High-Performance Pockels Effect-Based Modulators: Review and Projections

The ever-increasing demand for high-speed data transmission in telecommunications and data centers has driven the development of advanced on-chip integrated electro-optic modulators. Silicon modulators, constrained by the relatively weak carrier dispersion effect, face challenges in meeting the stringent requirements of next-generation photonic integrated circuits. Consequently, there has been a growing interest in Pockels effect-based electro-optic modulators, leveraging ferroelectric materials like LiNbO3, BaTiO3, PZT, and LaTiO3. Attributed to the large first-order electro-optic coefficient, researchers have delved into developing modulators with expansive bandwidth, low power consumption, compact size, and linear response. This paper reviews the working principles, fabrication techniques, integration schemes, and recent highlights in Pockels effect-based modulators.

Ultracompact parabolic sidewall-profiled hybrid plasmonic waveguide Bragg grating with optimized spectral properties of long-wavelength passband

An ultracompact hybrid plasmonic waveguide Bragg grating (HPWBG) with improved spectral properties of long-wavelength passband is proposed. A hollow HPW is introduced to suppress the entire loss, and a parabolic profiled sidewall is designed to optimize the spectral properties for specific wave bands. The transfer matrix method and finite element method are combined to ensure the efficiency of numerical research. The results show that the parabolic profile effectively reduces the reflection and strengthens the resonance of the mode in the long-wavelength passband, suppressing the oscillations and realizing significant smoothness and improvement in transmission. The optimized transmittance is greater than 99%, and insertion loss is as low as 0.017 dB. A wide bandgap of 103 nm is also attained. The structure also has a compactness with a length of 3.4 µm and exhibits good tolerance. This work provides a scheme for designing and optimizing wavelength selecting devices and has potential application value in integrated photonic devices.

Breakthrough in Silicon Photonics Technology in Telecommunications, Biosensing, and Gas Sensing

Silicon photonics has been an area of active research and development. Researchers have been working on enhancing the integration density and intricacy of silicon photonic circuits. This involves the development of advanced fabrication techniques and novel designs to enable more functionalities on a single chip, leading to higher performance and more efficient systems. In this review, we aim to provide a brief overview of the recent advancements in silicon photonic devices employed for telecommunication and sensing (biosensing and gas sensing) applications.

Design and Realization of Polymeric Waveguide/Microring Structures for Telecommunication Domain

Polymer-based micro-optical components are very important for applications in optical communication. In this study, we theoretically investigated the coupling of polymeric waveguide and microring structures and experimentally demonstrated an efficient fabrication method to realize these structures on demand. First, the structures were designed and simulated using the FDTD method. The optical mode and loss in the coupling structures were calculated, thereby giving the optimal distance for optical mode coupling between two rib waveguide structures or for optical mode coupling in a microring resonance structure. Simulations results then guided us in the fabrication of the desired ring resonance microstructures using a robust and flexible direct laser writing technique. The entire optical system was thus designed and manufactured on a flat base plate so that it could be easily integrated in optical circuits.

Polarization-insensitive antisymmetric multimode waveguide Bragg grating filter based on an SiN-Si dual-layer stack

A polarization-insensitive multimode antisymmetric waveguide Bragg grating (MASWBG) filter based on an SiN-Si dual-layer stack is demonstrated. Carefully optimized grating corrugations patterned on the sidewall of a silicon waveguide and SiN overlay are used to perturbate TE and TM modes, respectively. Furthermore, the lateral-shift apodization technique is utilized to improve the sidelobe suppression ratio (SLSR). A good overlap between the passbands measured in TE and TM polarization states is obtained. Insertion losses, SLSRs, and 3-dB bandwidths of measured passbands in TE/TM polarizations are 1/1.72 dB, 18.5/19.1 dB, and 5.1/3.5 nm, respectively.