AlScN-integrated microring resonators for enhanced piezo-photoelastic tuning

Piezo-photoelastic tuning provides a capacitive, carrier-free route to optical resonance control, making it attractive for data-center interconnects and energy-efficient photonics. However, piezoelectric materials that simultaneously provide lead-free composition, CMOS compatibility, and high piezoelectric coefficients remain elusive. To address this, we first propose and experimentally demonstrate AlScN-integrated Si₃N₄ microring resonators for efficient piezo-photoelastic tuning. The device employs a planar AlScN-on-Si₃N₄ stack designed to enhance stress-optical interaction. Experimental results show a passive loaded quality factor of 4.7×10⁴ and tuning efficiencies of 0.9 and 1.0 pm/V at the drop and through ports, respectively. These results demonstrate the potential of AlScN-integrated waveguides for enhanced piezo-photoelastic tuning.