Comparison of PZT Ceramic and PZN‐PT, LiNbO ₃ Single Crystals for Electromagnetic Radiation as Mechanical Antenna

Electromagnetic radiation in the low‐frequency (LF, 30–300 kHz) regime is vital for long‐range communication due to its unparalleled penetration through dissipative media. However, the prohibitively large dimensions of conventional antennas at these wavelengths preclude portability. Piezoelectric mechanical antennas (PMAs), which exploit strain‐driven currents, can reduce the antenna dimensions by up to five orders of magnitude compared to conventional antennas. Despite recent progress, systematic comparisons between ceramic‐ and single‐crystal‐based PMAs remain limited. Here, we present a comprehensive study of PMAs fabricated from PZT ceramics, LiNbO ₃ (LN) single crystals, and PZN‐PT single crystals. We integrate theoretical modeling and experimental characterization to establish a unified framework that links material properties with antenna radiation performance. Our results reveal that PZT4 ceramics and LN single crystals outperform other counterparts in terms of radiation efficiency and communication stability, while PZN‐PT offers giant piezoelectric coefficients but suffers from thermal instability and low Q . Furthermore, we demonstrate amplitude‐shift keying (ASK) modulation, confirming the feasibility of wireless communication using these compact antennas. This study provides the first head‐to‐head comparison between different piezoelectric materials (with the same size and electric field), offering key physical criteria for material selection for next‐generation LF portable communication systems in underwater, underground, and biomedical applications.