A multi-period-delayed feedback (MPDF) photonic circuit constructed by a Sagnac ring and two coupled rings was designed. By coupling a distributed feedback (DFB) laser diode (LD) with the MPDF, a narrow linewidth semiconductor laser was demonstrated. The linewidth of the DFB-LD with MPDF was narrowed to be around 2 kHz, which is reduced by three orders of magnitude, and the linewidth reduction capability could be maintained when the wavelength of the DFB-LD was tuned in a range wider than 3 nm. The laser frequency stability can also be improved using the proposed technique, and the frequency fluctuation was reduced for nearly 8 times in comparison with the DFB-LD.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1364/OE.458327 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Observation of NMR signals from samples with flat geometry: Application to in-situ analysis of a direct ethanol fuel cell.
J Magn Reson
January 2025
Department of Chemistry, Seoul National University, Seoul 08826 Republic of Korea; Advanced Institutes of Convergence Technology, Suwon 16229 Republic of Korea. Electronic address:
Most NMR samples are cylindrical, which is ideal for obtaining high-resolution NMR spectra, especially in superconducting magnets with a vertical bore. However, expanding NMR applicability to samples that are not necessarily cylindrical requires a new approach. In this study, we introduce a method for obtaining solution NMR signals from flat samples, such as flat containers or layered structures like a fuel cell.
View Article and Find Full Text PDFOptical clocks require an ultra-stable laser to probe and precisely measure the frequency of the narrow-linewidth clock transition. We introduce a portable ultraviolet (UV) laser system for use in an aluminum quantum logic clock, demonstrating a fractional frequency instability of approximately mod = 2 × 10. The system is based on an ultra-stable cavity with crystalline AlGaAs/GaAs mirror coatings, with a frequency quadrupling system employing two single-pass second-harmonic generation (SHG) stages.
View Article and Find Full Text PDFThis study proposes and experimentally demonstrates a distributed feedback (DFB) laser with a distributed phase shift (DPS) region at the center of the DFB cavity. By modeling the field intensity distribution in the cavity and the output spectrum, the DPS region length and phase shift values have been optimized. Experimental comparisons with lasers using traditional π-phase shifts confirm that DFB lasers with optimized DPS lengths and larger phase shifts (up to 15π) achieve stable single longitudinal mode operation over a broader current range, with lower threshold current, higher power slope efficiency, and a higher side mode suppression ratio (SMSR).
View Article and Find Full Text PDFScalable Synthesis of 2D ErOCl with Sub-meV Narrow Emissions at Telecom Band.
Adv Mater
January 2025
School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China.
Van der Waals (vdWs) materials are promising candidates for hetero-integration with silicon photonics toward miniaturization and integration. VdWs materials like molybdenum telluride and black phosphorus, despite being prominent, exhibit air sensitivity, and their room temperature emissions can be significantly broadened by tens of meV. Here, a self-encapsulation strategy is developed to scalably synthesize robust 2D vdWs ErOCl with sub-meV narrow emissions at the telecom C-band.
View Article and Find Full Text PDFAn ultra-narrow-linewidth laser is a core device in fields such as optical atomic clocks, quantum communications, and microwave photonic oscillators. This paper reports an ultra-narrow-linewidth self-injection locked semiconductor laser, which is realized through optical feedback from a high-Q (258 million) Fabry-Perot (FP) cavity constructed with three mirrors, generating an output power of 12 mW. Employing a delay self-heterodyne method based on a signal source analyzer, the phase noise of the laser is -129 dBc/Hz at 100 kHz offset frequency, with an intrinsic linewidth of 3 mHz.
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!