Mechanical Resonance Multiplexed Magnetic Communication via Magnetoelastic Heterostructured WGM Resonator

Magnetic communication offers stable signal propagation in non-line-of-sight, underwater, and cross-medium environments. Optical whispering gallery mode (WGM) resonators, known for their ultrahigh quality factors and sensitivity to weak perturbations, inherently support multiple mechanical modes and can be used for multi-channel parallel magnetic communication. However, the mechanical resonance modes are sparsely distributed and exhibit inconsistent response strengths, which limits the number and reliability of available communication channels. Therefore, we introduce a magneto- elastic heterostructured resonator integrating Terfenol-D to enhance magnetoelastic coupling, which significantly augments the density of frequency domain communication channels with nearly uniform response. Experimental results demonstrate the use of 10 parallel mechanical subcarriers to achieve a total data rate of 12.5 kbps—an order-of-magnitude improvement over single channel designs—with potential for further scalability. By employing multimodal resonance multiplexing with a microcavity-based sensor, our work establishes a new paradigm for high-capacity, short-range magnetic communication in complex environments.