Aluminum nitride waveguide beam splitters for integrated quantum photonic circuits

We demonstrate integrated photonic circuits for quantum devices using sputtered polycrystalline aluminum nitride (AlN) on insulator. On-chip AlN waveguide directional couplers, which are one of the most important components in quantum photonics, are fabricated and show the output power splitting ratios from 50:50 to 99:1. Polarization beam splitters with an extinction ratio of more than 10 dB are also realized from the AlN directional couplers. Using the fabricated AlN waveguide beam splitters, we observe Hong-Ou-Mandel interference with a visibility of 91.7% & PLUSMN; 5.66%. & COPY; 2023 Chinese Laser Press

Automated summary

We have fabricated integrated photonic circuits for quantum devices using sputtered polycrystalline aluminum nitride (AlN) on insulator. The on-chip AlN waveguide directional couplers, which are crucial components in quantum photonics, exhibit output power splitting ratios ranging from 50:50 to 99:1. Additionally, polarization beam splitters with an extinction ratio over 10 dB have been achieved using the AlN directional couplers. By employing the fabricated AlN waveguide beam splitters, we have observed Hong-Ou-Mandel interference with a visibility of 91.7%±5.66%.