A hybrid spiral-ring laser vertically coupled to a silicon waveguide is demonstrated to achieve stable and unidirectional output theoretically and experimentally. The mode competition between clockwise (CW) and counter-clockwise (CCW) modes is eliminated due to the mode coupling in a spiral resonator. The simulation results indicate that the CCW and CW direction traveling waves are dominant components, respectively, for the spiral resonator without and with an output waveguide. A hybrid AlGaInAs/Si spiral-ring laser is designed and fabricated vertically coupled to a silicon waveguide. For a spiral-ring laser with a radius of 30 μm and a ring width of 5 μm, the continuous-wave lasing threshold of 9.5 mA is obtained with the threshold current density of 1.1 kA/cm(2) at a temperature of 285 K. The output power fluctuations due to the mode competition between CW and CCW modes are eliminated. The output power from CCW direction is five times that from CW direction.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1364/OL.40.004995 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Novel RFID Multi-Label Network Location Measurement by Dual CCD and Non-Local Means-Harris Algorithm.
Sensors (Basel)
January 2025
Peking University Yangtze River Delta Institute of Optoelectronics, Nantong 100871, China.
To improve the performance of Radio Frequency Identification (RFID) multi-label systems, the multi-label network structure needs to be quickly located and optimized. A multi-label location measurement method based on the NLM-Harris algorithm is proposed in this paper. Firstly, multi-label geometric distribution images are obtained through a label image acquisition system of a multi-label semi-physical simulation platform with two vertical Charge-Coupled Device (CCD) cameras, and Gaussian noise is added to the image to simulate thermoelectric interference.
View Article and Find Full Text PDFIn order to understand the spatial distribution, influencing factors, pollution level and sources of heavy metals in black soil profiles in Northeast China, black soil profile samples were collected from five sampling points in Haicheng City, Liaoning Province, with the deepest profile depth of 50m. The contents of heavy metals (As, Cd, Cr, Cu, Hg, Ni, Pb and Zn) in soil at different depths were analyzed, and the distribution characteristics and influencing factors of heavy metals in black soil profiles were analyzed. The pollution level of heavy metals in soil was evaluated based on the geo-accumulation index method and enrichment factor method, and the sources of heavy metals in soil were analyzed based on principal component analysis.
View Article and Find Full Text PDFA Highly Correlated, Multireference Study of the Lowest Lying Singlet and Triplet States of the Four Thiophene Diradicals.
J Comput Chem
January 2025
Department of Chemistry, Gottwald Center for the Sciences, University of Richmond, Richmond, Virginia, USA.
The energies and geometries of the lowest lying singlet and triplet states of the four diradicals formed by removing two H atoms from thiophene have been characterized. We utilized the highly correlated, multireference methods configuration interaction with single and double excitations with and without the Pople correction for size-extensivity (MR-CISD+Q and MR-CISD) and averaged quadratic coupled cluster theory (MR-AQCC). CAS (8,7) and CAS (10,8) active spaces involving σ, σ*, π, and π* orbitals were employed along with the cc-pVDZ and cc-pVTZ basis sets.
View Article and Find Full Text PDFA Study on Dust Storm Pollution and Source Identification in Northwestern China.
Toxics
January 2025
Key Laboratory of Cryospheric Science and Frozen Soil Engineering, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China.
In April 2023, a major dust storm event in Lanzhou attracted widespread attention. This study provides a comprehensive analysis of the causes, progression, and dust sources of this event using multiple data sources and methods. Backward trajectory analysis using the HYSPLIT model was employed to trace the origins of the dust, while FY-2H satellite data provided high-resolution dust distribution patterns.
View Article and Find Full Text PDFCompact inverse designed vertical coupler with bottom reflector for sub-decibel fiber-to-chip coupling on silicon on insulator platform.
Sci Rep
January 2025
Institute for Functional Matter and Quantum Technologies, University of Stuttgart, 70569, Stuttgart, Germany.
Inverse design via topology optimization has led to innovations in integrated photonics and offers a promising way for designing high-efficiency on-chip couplers with a minimal footprint. In this work, we exploit topology optimization to design a compact vertical coupler incorporating a bottom reflector, which achieves sub-decibel coupling efficiency on the 220-nm silicon-on-insulator platform. The final design of the vertical coupler yields a predicted coupling efficiency of -0.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!