Hybrid integrated near UV lasers using the deep-UV Al2O3 platform

• Main Authors: Franken, C. A. A, Hendriks, W. A. P. M, Winkler, L. V, Dijkstra, M, NascimentoJr, A. R. do, van Rees, A, Mardani, M. R. S, Dekker, R, van Kerkhof, J, van der Slot, P. J. M, García-Blanco, S. M, Boller, K. -J
• Format: Journal Article
• Language: English
• Published: 22-02-2023
• Subjects: Physics - Applied Physics; Physics - Optics
• DOI: 10.48550/arxiv.2302.11492

Hybrid integrated diode lasers have so far been realized using silicon,
polymer, and silicon nitride (Si3N4) waveguide platforms for extending on-chip
tunable light engines from the infrared throughout the visible range. Here we
demonstrate the first hybrid integrated laser using the aluminum oxide (Al2O3)
deep-UV capable waveguide platform. By permanently coupling low-loss Al2O3
frequency-tunable Vernier feedback circuits with GaN double-pass amplifiers in
a hermetically sealed housing, we demonstrate the first extended cavity diode
laser (ECDL) in the near UV. The laser shows a maximum fiber-coupled output
power of 0.74 mW, corresponding to about 3.5 mW on chip, and tunes more than
4.4 nm in wavelength from 408.1 nm to 403.7 nm. Integrating stable, single-mode
and tunable lasers into a deep-UV platform opens a new path for chip-integrated
photonic applications.