The quantum cascade laser (QCL), a potential laser source for mid-infrared applications, has all of the advantages of a semiconductor laser, such as small volume and light weight, and is driven by electric power. However, the optical power of a single QCL is limited by serious self-heating effects. Therefore, beam combination technology is essential to achieve higher laser powers. In this letter, we demonstrate a simple beam combination scheme using two QCLs to extend the output peak power of the lasers to 2.3 W. A high beam combination efficiency of 89% and beam quality factor of less than 5 are also achieved.
© 2013 Chinese Optics Letters
Lasers and Laser Optics
Hao Wu, Lijun Wang, Fengqi Liu, Hangyu Peng, Jun Zhang, Cunzhu Tong, Yongqiang Ning, and Lijun Wang, "High efficiency beam combination of 4.6-\mu m quantum cascade lasers," Chin. Opt. Lett. 11, 091401- (2013)