Broadband 2-µm emission on silicon chips: monolithically integrated Holmium lasers

• Main Authors: Li, Nanxi (Author), Magden, Emir Salih (Author), Su, Zhan (Author), Singh, Neetesh (Author), Ruocco, Alfonso (Author), Xin, Ming (Author), Byrd, Matthew James (Author), Callahan, Patrick T. (Author), Bradley, Jonathan (Author), Baiocco, Christopher (Author), Vermeulen, Diedrik Rene Georgette (Author), Watts, Michael (Author)
• Other Authors: Massachusetts Institute of Technology. Research Laboratory of Electronics (Contributor), Lincoln Laboratory (Contributor)
• Format: Article
• Language: English
• Published: Optical Society of America (OSA), 2021-02-17T19:38:12Z.
• Subjects: Article
• Online Access: Get fulltext

Laser sources in the mid-infrared are of great interest due to their wide applications in detection, sensing, communication and medicine. Silicon photonics is a promising technology which enables these laser devices to be fabricated in a standard CMOS foundry, with the advantages of reliability, compactness, low cost and large-scale production. In this paper, we demonstrate a holmium-doped distributed feedback laser monolithically integrated on a silicon photonics platform. The Al₂O₃:Ho³⁺ glass is used as gain medium, which provides broadband emission around 2 µm. By varying the distributed feedback grating period and Al₂O₃:Ho³⁺ gain layer thickness, we show single mode laser emission at wavelengths ranging from 2.02 to 2.10 µm. Using a 1950 nm pump, we measure a maximum output power of 15 mW, a slope efficiency of 2.3% and a side-mode suppression ratio in excess of 50 dB. The introduction of a scalable monolithic light source emitting at < 2 µm is a significant step for silicon photonic microsystems operating in this highly promising wavelength region.
Defense Advanced Research Projects Agency (Grants HR0011- 12-2-0007 and HR0011-15-C-0056)