A Novel Intra-Cavity Lens Design for Compact High Efficiency Tapered Laser Diodes

• Main Authors: Lau, F. K., TEE, Chyng Wen, Penty, R. V., White, I. H., Michel, N., Krakowski, M.
• Format: text
• Language: English
• Published: Institutional Knowledge at Singapore Management University 2007
• Subjects: Beam quality; Gaussian beam; catastrophic optical mirror damage (COMD); diverging lens; high-brightness lasers; high-power lasers; integrated lens; mode expansion; tapered lasers; Physical Sciences and Mathematics
• Online Access: https://ink.library.smu.edu.sg/lkcsb_research/3339; https://ink.library.smu.edu.sg/context/lkcsb_research/article/4338/viewcontent/Novel_Intracavity_Lens_2007.pdf
• Institution: Singapore Management University

An integrated parabolic lens capable of introducing a diverging effect to the optical mode propagating within the cavity of a tapered laser is proposed and demonstrated. This idea allows broader high-power beams to be generated by shorter cavities. Diverging lenses with etch depths of 0.13 and 0.27 mum are implemented, with 12 (9.5%) and 16.8 mum (13.3%) overall broadening of the near-fields widths measured at 1/e2 intensity. The peak output power as well as the threshold current is found to increase following the lens etching process, confirming the beneficial broadening effect introduced by the diverging lens.