Multi-Channel Amplitude-Phase Asymmetric-Encrypted Janus Acoustic Meta-Holograms

Haohan Zeng; Zhenyu He; Tianxiang Zhang; Xiao Guo; Xinghao Hu; Youyu Mo; Tingting Li; Feilong Mao; Haiyan Fan; Xudong Fan; Weiwei Kan; Yifan Zhu; Hui Zhang; Guodong Yin; Badreddine Assouar

arXiv · 2510.05789

Multi-Channel Amplitude-Phase Asymmetric-Encrypted Janus Acoustic Meta-Holograms

Haohan Zeng·Zhenyu He·Tianxiang Zhang·Xiao Guo·Xinghao Hu·Youyu Mo·Tingting Li·Feilong Mao·Haiyan Fan·Xudong Fan·Weiwei Kan·Yifan Zhu·Hui Zhang·Guodong Yin·Badreddine Assouar

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Abstract

Encrypted optical and acoustic meta-holograms only focus on the encrypted hologram in a single channel, viz. modulating spatial amplitude to project a holographic image. In this research, the unique concept of multi-channel amplitude-phase asymmetric-encrypted Janus acoustic meta-holograms is proposed, demonstrating remarkable capabilities of generating, encrypting, and decrypting both amplitude and phase holographic images on both sides of a metascreen. The flexible and decoupled manipulation mechanism for the amplitude-phase of the bidirectional acoustic waves used in our concept offers multiple possibilities to apply various encryption methods. In this work, our system enables single-input, two-faced four-channel asymmetric encryption, which substantially increase the communication capacity of conventional acoustic holograms, and establish a security framework based on mathematical problem, proving its security. Our work can lead to concrete applications including, but not limited to, multi-channel acoustic field communications and acoustic illusion and cloaking in non-transparent media.

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Haohan Zeng, Zhenyu He, Tianxiang Zhang, Xiao Guo, Xinghao Hu, Youyu Mo, Tingting Li, Feilong Mao, Haiyan Fan, Xudong Fan, Weiwei Kan, Yifan Zhu, Hui Zhang, Guodong Yin, Badreddine Assouar. 2025-10-07. Multi-Channel Amplitude-Phase Asymmetric-Encrypted Janus Acoustic Meta-Holograms. https://arxiv.org/abs/2510.05789

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