Resonance-shifted DFB-LD for asymmetric light output from front/rear facets
| Autor: | Kei-ichiro Ichikawa, Takahiro Numai |
|---|---|
| Rok vydání: | 2016 |
| Předmět: |
Materials science
business.industry Mode (statistics) Resonance 02 engineering and technology 021001 nanoscience & nanotechnology Laser 01 natural sciences Atomic and Molecular Physics and Optics Electronic Optical and Magnetic Materials law.invention 010309 optics Longitudinal mode Semiconductor Optics law Optical cavity 0103 physical sciences Optoelectronics Electrical and Electronic Engineering 0210 nano-technology business Diffraction grating Lasing threshold |
| Zdroj: | Optik. 127:6253-6257 |
| ISSN: | 0030-4026 |
| DOI: | 10.1016/j.ijleo.2016.04.090 |
| Popis: | To obtain asymmetric light output from front/rear facets in a semiconductor laser maintaining single longitudinal mode (SLM) operation, a resonance-shifted DFB-LD is proposed and its lasing characteristics are simulated. The laser cavity of the resonance-shifted DFB-LD is divided into two regions. Each region has uniform diffraction gratings, and the corrugation pitch of region 1 is different from that of region 2. By adjusting the corrugation pitches of the two regions, a resonance mode in region 1 and that in region 2 are overlapped. At the overlapped resonance mode, SLM operation is obtained. When the corrugation pitch difference is 0.3 nm with κL1 = κL2 = 3 where κ is the grating coupling coefficient; length L1 of region 1 and length L2 of region 2 are about 560 μm, the normalized threshold gain difference was 0.509, which is large enough for SLM operation. Under this condition, the light output ratio from the front/rear facets is 5.69. This light output ratio is larger than the highest value of 2.6, which was achieved in a phase-shifted DFB-LD with asymmetrically-pitch-modulated gratings. |
| Databáze: | OpenAIRE |
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