| Author: | Su, Zhiyao |
| Title: | Single-frequency tunable fiber laser covering C+L band |
| Advisors: | Huang, Dongmei (EEE) |
| Degree: | M.Sc. |
| Year: | 2023 |
| Department: | Department of Electrical and Electronic Engineering |
| Pages: | 1 volume (various pagings) : color illustrations |
| Language: | English |
| Abstract: | Tunable ultra-narrow linewidth lasers are important for applications in precision optical sensing and spectroscopy, and wavelength division multiplexing coherence transmission. Full C-band or L-band wavelength tunable laser diodes such as external cavity, sampled grating distributed Bragg reflector and distributed feedback laser array etc., have been proposed. However, the linewidth is limited due to the short cavity length. Fiber lasers using Er³⁺-doped fiber as the gain can overcome the problem and realize narrow linewidth. Conventional tunable lasers usually cover C-band or L-band because the luminescence center and net gain of ordinary Er³⁺-doped fiber (EDF) are located in either C-band or L-band only, which makes it difficult to realize a wide tuning range covering both C- and L-band. In this thesis, we propose and demonstrate a novel scheme to achieve a C- and L-band tunable ultra-narrow linewidth ring fiber laser by utilizing the Er³⁺-doped fiber. The active optical fiber in the laser is made by Si with Sb ions, and its output spectrum covers the C+L bands. The constructed continuous wave laser has a wide tuning range, ultra-high optical signal-to-noise ratio (OSNR), and ultra-narrow linewidth by combining a sub-ring and a saturable absorber. The single frequency laser has around 500 Hz linewidth, 80 dB OSNR, and a side-mode suppression ratio (SMSR) of 60 dB, with a tuning range from 1530 nm to 1606 nm. |
| Rights: | All rights reserved |
| Access: | restricted access |
Files in This Item:
| File | Description | Size | Format | |
|---|---|---|---|---|
| 8950.pdf | For All Users (off-campus access for PolyU Staff & Students only) | 2.29 MB | Adobe PDF | View/Open |
Copyright Undertaking
As a bona fide Library user, I declare that:
- I will abide by the rules and legal ordinances governing copyright regarding the use of the Database.
- I will use the Database for the purpose of my research or private study only and not for circulation or further reproduction or any other purpose.
- I agree to indemnify and hold the University harmless from and against any loss, damage, cost, liability or expenses arising from copyright infringement or unauthorized usage.
By downloading any item(s) listed above, you acknowledge that you have read and understood the copyright undertaking as stated above, and agree to be bound by all of its terms.
Please use this identifier to cite or link to this item:
https://theses.lib.polyu.edu.hk/handle/200/14521