2021/04/13 by Mishra, Jatadhari, McKenna, Timothy P., Ng, Edwin +7 · 3 citations
#FOS: Physical sciences #Optics (physics.optics)
paper · doi:10.48550/arxiv.2104.05990
Periodically poled thin-film lithium niobate (TFLN) waveguides have emerged as a leading platform for highly efficient frequency conversion in the near-infrared. However, the commonly used silica bottom-cladding results in high absorption loss at wavelengths beyond 2.5 μm. In this work, we demonstrate efficient frequency conversion in a TFLN-on-sapphire platform, which features high transparency up to 4.5 μm. In particular, we report generating mid-infrared light up to 3.66 μm via difference-frequency generation of a fixed 1-μm source and a tunable telecom source, with normalized efficiencies up to 200%/W-cm2. These results show TFLN-on-sapphire to be a promising platform for integrated nonlinear nanophotonics in the mid-infrared.