What is the main mechanism responsible for losses in silicon waveguides?
Best insight from top research papers
The main mechanisms responsible for losses in silicon waveguides include free-carrier absorption (FCA), Rayleigh scattering, Mie scattering, two-photon absorption (TPA), and linear propagation loss. FCA, caused by electron-hole pairs generated by high-level generation events, contributes to transient loss. Rayleigh scattering and Mie scattering are observed in waveguides written in fused silica, with Rayleigh scattering improving after thermal annealing. TPA, FCA, and linear propagation loss significantly affect insertion loss in silicon waveguides, with larger mode areas and reduced linear propagation loss being effective in minimizing losses. Additionally, submicron silicon-on-insulator waveguides exhibit propagation loss due to lattice defects, which can be mitigated through thermal annealing.
Answers from top 4 papers
More filters
| Papers (4) | Insight |
|---|---|
17 Citations | Loss mechanisms in silicon waveguides are primarily due to Rayleigh scattering and coupling losses, influenced by pulse energy, scan velocity, and annealing temperature, as per the research findings. |
| Polarization-dependent losses, causing filtering of light polarization and attenuation of transverse electric mode, are the main mechanisms in porous silicon ridge waveguides, as per the research findings. | |
05 Nov 2020 1 Citations | The main mechanisms responsible for losses in silicon waveguides are two-photon absorption (TPA), free-carriers absorption (FCA), and linear propagation loss, as highlighted in the research paper. |
| The main mechanisms for losses in silicon waveguides at 2 μm are propagation loss, waveguide bending loss, and doped waveguide loss, with thermal annealing addressing lattice defects from ion-implantation. |
Related Questions
Is SiGe waveguide a thing for silicon photonics?5 answersSiGe waveguides have been extensively studied in the field of silicon photonics. They have been used in on-chip optical links, demonstrating optical coupling of up to 5 GHz with a total optical link budget loss of -40 dB. SiGe detectors with detection efficiencies of up to 0.85 have been integrated with Si avalanche-mode optical sources, enabling the realization of low-cost on-chip optical signal processing and optical interconnects. Additionally, SiGe avalanche photodiodes with lateral separated absorption and multiplication (SAM) structures have been demonstrated to have clear open eye diagrams at 10 Gbps, making them suitable for next-generation optical access network systems. SiGe photodetectors with Ge-phoxonic crystal cavities have shown enhanced absorption efficiency over a broad range of midwave infrared spectrum. Overall, SiGe waveguides have shown promise in various applications within silicon photonics.
Waveguide material for silicon photonics?4 answersSilicon, silicon nitride, and silica are the main materials used for waveguides in silicon photonics applications. These materials have attracted significant interest from academia and industry due to their optical properties and widespread applications. In addition to these traditional materials, new opto-electronic materials such as 2D materials, thin-film lithium niobate, and alumina are also being explored for hybrid integration with silicon to achieve new functions or superior performance. Another promising waveguide material for silicon photonics is thick-SOI technology, which offers lower propagation loss, reduced polarization sensitivity, and efficient edge coupling. Subwavelength engineered metamaterial waveguides are also being considered as fundamental building blocks for integrated photonic circuits. Furthermore, SiN waveguides have been used for ultralow-loss fiber coupling structures and Si-to-SiN waveguides for C-band infrared light on a Si photonics platform. Finally, a hybrid waveguide made of hexagonal boron nitride (hBN) and silicon has been demonstrated to enable dual-band operation at mid-infrared and telecom frequencies, expanding the functionality of silicon photonics.
How the propagation of electromagnetic waves in lossy media can be studied?5 answersThe propagation of electromagnetic waves in lossy media can be studied using various methods. One approach is to analyze the incidence of an inhomogeneous plane wave on the interface between two lossy media. This allows for the determination of the incidence angle of the phase vector, which affects the behavior of the transmitted wave. Another method involves applying the complex two-dimensional stationary-phase method to problems of electromagnetic wave radiation in dispersive and lossy media. This approach provides explicit formulas for fields generated by moving sources and allows for the study of phenomena such as the Doppler effect and Cherenkov radiation. Additionally, the use of theoretical propagation equations can help calculate the propagation constants of electromagnetic waves in lossy human tissues. These calculations provide valuable data for designing microwave applicators for medical applications.
What is path loss?4 answersPath loss refers to the attenuation of a wireless signal as it travels from the transmitting antenna to the receiver. It occurs due to external field conditions and is an important factor in telecommunication design. One study by Sukemi et al. used a machine learning-based path loss prediction model called random forest to calculate path loss in a 4G network. Path-loss models are widely used in channel propagation analysis, including in mmWave systems. Another paper by Ellingson discussed path loss in the context of reconfigurable intelligent surfaces (RIS), which use controllable elements to scatter signals in a desired way. Additionally, a study on signal strength variation in a hilly-forested region found a relationship between path loss and line of sight analysis, mean elevation, and regression loss models.
What are the cause of high energy losses?4 answersHigh energy losses can occur due to several reasons. One main cause is the system design, which often requires oversizing of the photovoltaic (PV) array to meet the load demand during the winter season when solar energy is limited. Mismatch between the PV array and the load or battery can also lead to energy loss. Additionally, energy loss can occur in batteries and due to PV array disconnect, especially during the summer season when the battery is fully charged. In the case of thickness fringes in electron microscopy, energy loss can result in a loss of fringe contrast. In fluid dynamics, energy losses can occur due to friction between the liquid and the wetted surfaces of pipes, changes in flow direction, and resistance from fittings and changes in pipe diameter. In a current-carrying plasma, energy loss is attributed to the drift motion of particles interacting with ion-acoustic wave instabilities.
What is transmission loss?5 answersTransmission loss refers to the loss in the flow volume of a river as water moves downstream. It is an important factor in ephemeral and intermittent river systems, providing crucial ecosystem services. Transmission losses can be measured using various techniques, such as differential gauging of river flow at two locations or visual assessments of the wetted river length on satellite images. In the case of the Selwyn River in Canterbury, New Zealand, transmission losses were estimated using satellite images and verified through field observations and differential gauging campaigns. The results showed that the transmission losses in the Selwyn River ranged between 0.25 and 0.65 m3/s/km during most of the study period, with higher losses observed shortly after flood peaks. This research improved the understanding of groundwater-surface water interactions in the Selwyn River and provided valuable data for water management.