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.

Tunable Narrow Linewidth External Cavity Diode Laser Employing Wide Interference Filter and Diffraction Grating

“…As seen in Figure 1, the beam splitter (BS) is used to measure the optical power, optical spectrum and linewidth. We employ the delayed self-heterodyne technique to measure the laser linewidth, as shown in Figure 1 [17]. The length difference of two interferometer fiber arms needs to be large enough to ensure its accuracy and sensitivity.…”

Stability-enhanced RF signal transmission over long fiber-optic links

“…The laser is a core component of the phase stability system, and its output characteristics directly affect stable phase transmission. Parameters like laser linewidth, frequency stability, and output power influence the phase noise characteristics of the system [12][13][14][15][16] . Choosing a laser with lower linewidth and frequency drift can improve the phase stability of the system.…”