Title :
High-Power Single-Mode Tapered Terahertz Quantum Cascade Lasers
Author :
Tao Wang ; Junqi Liu ; Fengqi Liu ; Lijun Wang ; Jinchuan Zhang ; Zhanguo Wang
Author_Institution :
Key Lab. of Semicond. Mater. Sci., Inst. of Semicond., Beijing, China
Abstract :
We demonstrate a series of high output power single-mode terahertz quantum cascade lasers based on semi-insulating surface-plasmon waveguide with tapered geometry structure. The taper half-angle is ranging from 0° to 3°. The tapered waveguide effects on the output power and the laser beam quality are experimentally studied. High single longitudinal mode edge-emission peak powers (92.3 mW) are realized. The peak power monolithically increases with the increasing of the taper angle. All distributed feedback (DFB) lasers lased in the temperature range of 70-75 K. The highest brightness is obtained from the 2° laser. Stable single-mode emissions are realized for DFB lasers with the side-mode suppression ratio $sim 18$ dB.
Keywords :
brightness; distributed feedback lasers; laser beams; laser modes; quantum cascade lasers; surface plasmons; waveguide lasers; DFB lasers; brightness; distributed feedback lasers; high output power single-mode terahertz quantum cascade lasers; high single longitudinal mode edge-emission peak powers; high-power single-mode tapered terahertz quantum cascade lasers; laser beam quality; power 92.3 mW; semiinsulating surface-plasmon waveguide; side-mode suppression ratio; stable single-mode emissions; taper half-angle; tapered geometry structure; tapered waveguide effects; temperature 70 K to 75 K; Laser beams; Laser modes; Laser theory; Measurement by laser beam; Power generation; Quantum cascade lasers; Distributed feedback lasers; Quantum cascade lasers; Single mode lasers; distributed feedback lasers; single mode lasers;
Journal_Title :
Photonics Technology Letters, IEEE
DOI :
10.1109/LPT.2015.2426697
