Ultralow-Loss Planar Si 3 N 4 Waveguide Polarizers Ultralow-Loss Planar Si 3 N 4 Waveguide Polarizers (original) (raw)
Related papers
A device library for the ultra-low loss Si3N4 platform
Silicon Photonics XVII, 2022
Silicon nitride platforms based on ultra-low loss tightly confining waveguides present a great interest for a wide range of applications. We present our 200mm platform based on 800nm-thick LPCVD Si3N4 with optical losses below 5dB/m. It is completed with a set of photonic components specially developed for this platform: grating and edge fiber couplers, directional couplers, MMI, Y-junction, racetrack resonators and an AWG multiplexer. The Si3N4 platform and its device library are the basic building blocks for more complex circuits targeting advanced applications: LiDAR, microwave optics, quantum photonics, neuromorphic computing and sensors.
Compact broadband polarizer based on shallowly-etched silicon-on-insulator ridge optical waveguides
Optics Express, 2010
A new way to make broadband polarizers on silicon-on-insulator (SOI) waveguides is proposed, analyzed and characterized. The characteristics of the eigenmodes in a shallowly-etched SOI ridge optical waveguide are analyzed by using a full-vectorial finite-different method (FV-FDM) mode solver. The theoretical calculation shows that the loss of TE fundamental mode could be made very low while at the same time the TM fundamental mode has very large leakage loss, which is strongly dependent on the trench width. The leakage loss of the TM fundamental mode changes quasi-periodically as the trench width w tr varies. The formula of the period ∆w tr is given. By utilizing the huge polarization dependent loss of this kind of waveguide, a compact and simple optical polarizer based on a straight waveguide was demonstrated. The polarizer is fabricated on a 700nm-thick SOI wafer and then characterized by using a free-space optical system. The measured extinction ratio is as high as 25dB over a 100nm wavelength range for a 1mm-long polarizer.
Low-Loss Si3N4 TriPleX Optical Waveguides: Technology and Applications Overview
IEEE Journal of Selected Topics in Quantum Electronics, 2018
An overview of the most recent developments and improvements to the low-loss TriPleX Si 3 N 4 waveguide technology is presented in this paper. The TriPleX platform provides a suite of waveguide geometries (box, double stripe, symmetric single stripe, and asymmetric double stripe) that can be combined to design complex functional circuits, but more important are manufactured in a single monolithic process flow to create a compact photonic integrated circuit. All functionalities of the integrated circuit are constructed using standard basic building blocks, namely straight and bent waveguides, splitters/combiners and couplers, spot size converters, and phase tuning elements. The basic functionalities that have been realized are: ring resonators and Mach-Zehnder interferometer filters, tunable delay elements, and waveguide switches. Combination of these basic functionalities evolves into more complex functions such as higher order filters, beamforming networks,
Ultra-low-loss high-aspect-ratio Si_3N_4 waveguides
Optics Express, 2011
We characterize an approach to make ultra-low-loss waveguides using stable and reproducible stoichiometric Si 3 N 4 deposited with lowpressure chemical vapor deposition. Using a high-aspect-ratio core geometry, record low losses of 8-9 dB/m for a 0.5 mm bend radius down to 3 dB/m for a 2 mm bend radius are measured with ring resonator and optical frequency domain reflectometry techniques. From a waveguide loss model that agrees well with experimental results, we project that 0.1 dB/m total propagation loss is achievable at a 7 mm bend radius with this approach.
IOSR Journal of Electrical and Electronics Engineering
Attenuation characteristics of a planar silicon-clad ion exchange glass waveguide structure are investigated theoretically at the optical wavelength of 0.6328 µm. An oscillatory behaviour of the attenuation curves is noticed in the proposed four layer structure. It is observed that by varying the thickness of silicon cladding layer, the TE or TM propagating modes may be selectively attenuated. This characteristic can be used to design a high extinction ratio and low insertion loss TE or TM pass polarizer. For the analysis of both polarizations, effective indices are calculated at various thicknesses of Silicon cladding layer using Transfer Matrix Method (TMM). At an optimum Silicon thickness, polarizer parameters like insertion loss and extinction ratio are calculated and tabulated. This paper provides rigorous analysis for silicon clad waveguide polarizer parameters for TE as well as TM polarization using same structure. A TM pass polarizer with extinction ratio of about 690 dB and insertion loss of about 2.8 dB and a TE pass polarizer with extinction ratio of about 289 dB and insertion loss of about 1.5 dB is proposed for a length of 1mm.
Light: Science & Applications, 2012
Silicon-based large-scale photonic integrated circuits are becoming important, due to the need for higher complexity and lower cost for optical transmitters, receivers and optical buffers. In this paper, passive technologies for large-scale photonic integrated circuits are described, including polarization handling, light non-reciprocity and loss reduction. The design rule for polarization beam splitters based on asymmetrical directional couplers is summarized and several novel designs for ultra-short polarization beam splitters are reviewed. A novel concept for realizing a polarization splitter-rotator is presented with a very simple fabrication process. Realization of silicon-based light non-reciprocity devices (e.g., optical isolator), which is very important for transmitters to avoid sensitivity to reflections, is also demonstrated with the help of magneto-optical material by the bonding technology. Low-loss waveguides are another important technology for large-scale photonic integrated circuits. Ultra-low loss optical waveguides are achieved by designing a Si 3 N 4 core with a very high aspect ratio. The loss is reduced further to ,0.1 dB m 21 with an improved fabrication process incorporating a high-quality thermal oxide upper cladding by means of wafer bonding. With the developed ultra-low loss Si 3 N 4 optical waveguides, some devices are also demonstrated, including ultra-high-Q ring resonators, low-loss arrayed-waveguide grating (de)multiplexers, and high-extinction-ratio polarizers.
Sidewall gratings in ultra-low-loss Si_3N_4 planar waveguides
Optics Express, 2013
We demonstrate sidewall gratings in an ultra-low-loss Si 3 N 4 planar waveguide platform. Through proper geometrical design we can achieve coupling constant values between 13 and 310 cm −1 . The TE waveguide propagation loss over the range of 1540 to 1570 nm is below 5.5 dB/m.
Ultra-Low-Loss Silicon Waveguides for Heterogeneously Integrated Silicon/III-V Photonics
2018
Integrated ultra-low-loss waveguides are highly desired for integrated photonics to enable applications that require long delay lines, high-Q resonators, narrow filters, etc. Here we present an ultra-low-loss silicon waveguide on 500 nm thick SOI platform. Meter-scale delay lines, million-Q resonators and tens of picometer bandwidth grating filters are experimentally demonstrated. We design a low-loss low-reflection taper to seamlessly integrate the ultra-low-loss waveguide with standard heterogeneous Si/III-V integrated photonics platform to allow realization of high-performance photonic devices such as ultra-low-noise lasers and optical gyroscopes.
Design, fabrication, structural and optical characterization of thin Si3N4 waveguides
2004
LPCVD (low pressure chemical vapor deposition) thin film Si 3 N 4 waveguides have been fabricated on Si substrate within a CMOS (complementary metal-oxidesemiconductor) fabrication pilot-line. Rib, channel, and striploaded waveguides have been designed, fabricated and characterized in order to workout the best structure. Number and optical confinement factors of guided optical modes have been simulated taking into account sidewall effects caused by the etching processes, which have been studied by Scanning Electron Microscopy. Optical guided modes have been observed with a mode analyzer and compared with simulation expectation to confirm the process parameters. Propagation loss measurements at 780 nm have been performed by using both the cut-back technique and measuring the drop of intensity of the top scattered light along the length of the waveguide. Loss coefficients of about 0.1 dB/cm have been obtained for channel waveguides. These data are very promising in view of the development of Si integrated photonics.
Single polarization optical waveguide on silicon
IEEE Journal of Quantum Electronics, 1991
A single polarization optical waveguide structure is introduced and demonstrated experimentally. The optical waveguide structure considered is a silicon nitride 6Im deposited onto an oxidized silicon wafer so as to form a single-mode planar waveguide. Single polarization is achieved by choosing layer thicknesses so that the attenuation due to substrate coupling for the TM mode is much larger than that for the TE mode. Calculations are presented to define ranges of design parameters over which TM attenuation can be 3-4 orders of magnitude higher than that for TE. In one sample having a TE loss of 0.28 dB/cm measured at a wavelength of 0.63 pm a ratio of TM to TE attenuation of over 750 is experimentally demonstrated.