Development of a High-Power Surface Grating Tunable Distributed-Feedback Bragg Semiconductor Laser Based on Gain-Coupling Effect

Abstract

Lasers used for space communication, lidar, and laser detection in space-air-ground integration applications typically use a traditional 1550 nm band tunable distributed-feedback Bragg (DFB) semiconductor laser. This has low output power, complex fabrication process, and high fabrication cost. In this paper, we present a gain-coupled surface grating-based 1550 nm DFB semiconductor laser that can be fabricated without the use of secondary epitaxial growth techniques or high-precision lithography. The periodic electrical injection is used to achieve a gain coupling effect. A tapered waveguide is added to achieve a high output power, and the use of AlGaInAs multiple quantum wells in the active region reduces the linewidth of the laser. A continuous-wave (CW)output power of 401.5 mW is achieved at 20 °C, the maximum side mode rejection ratio exceeds 55 dB, the measured 3 dB linewidth is 18.86 MHz, and the stable single-mode output with a quasi-continuous tuning range of 6.156 nm near 1550 nm from 10 °C to 50 °C. This simple preparation method, low cost, excellent performance, and stable tunable laser have extremely high commercial value in applications such as space communication, lidar, and laser detection.

Keywords

• 1550 nm
• tunable DFB semiconductor laser
• gain-coupled
• surface grating