Bidirectional Thermo-Acoustic Modulator Based on LiNbO₃ Thin Film

This letter presents a bidirectional thermo-acoustic (TA) modulator utilizing Y36-cut LiNbO $_{\mathbf {3}}$ thin film. The device integrates two TA phase modulators and a one-dimensional (1D) phase-control transducer within a compact footprint of less than 0.35 mm2. The suspended LN thin film TA phase modulator demonstrates a phase response of 17°/mW. The composed TA amplitude modulator supports bidirectional amplitude modulation, achieving over 30 dB modulation at 460 MHz with a control voltage of 1.1 V. This compact and efficient design makes it ideal for phononic integrated circuit (PnIC) and advanced acoustic signal processing applications. [2024-0162]