Mid-infrared nonlinear optics in thin-film lithium niobate on sapphire

• DOI: 10.1364/optica.427428
• Publication Date: 2021-05-27T21:00:09Z
• Authors: Jatadhari Mishra; Timothy P. McKenna; Edwin Ng; Hubert S. Stokowski; Marc Jankowski; Carsten Langrock; David Heydari; Hideo Mabuchi; M. M. Fejer; Amir H. Safavi-Na...
• Keywords: Optical materials

Periodically poled thin-film lithium niobate (TFLN) waveguides have emerged as a leading platform for highly efficient frequency conversion in the near-infrared. However, commonly used silica bottom-cladding results high absorption loss at wavelengths beyond 2.5 µm. In this work, we demonstrate TFLN-on-sapphire platform, which features transparency up to 4.5 particular, report generating mid-infrared light 3.66 µm via difference-frequency generation of fixed 1 source and tunable telecom source, with normalized efficiencies <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mn>200</mml:mn> <mml:mi mathvariant="normal">%</mml:mi> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:mo>/</mml:mo> </mml:mrow> mathvariant="normal">W</mml:mi> <mml:mspace width="thinmathspace"/> <mml:msup> mathvariant="normal">c</mml:mi> mathvariant="normal">m</mml:mi> <mml:mn>2</mml:mn> </mml:msup> </mml:math> . These show be promising integrated nonlinear nanophotonics mid-infrared.