Ions–Electrons Sensing Nerve Fiber for Visualization Tactile Biometric Encryption

Abstract

Smart home, through devices interconnection and collaboration, serves as a vehicle for building future intelligent lifestyles. Among them, the tactile-sensing encryption device can convert user-operated physical signals (e.g., pressure) into electrical signals, forming specific password sequences to achieve personalized information encryption. However, the above devices employ non-biometric encryption technology, facing the bottleneck of encryption sequences being easily cracked, which severely compromises the information security of users. Herein, inspired by the signaling transmission of biological synapse, a biometric tactile-sensing encrypted nerve fiber (BTENF) is fabricated by constructing a synapse-like coupling capacitance micro-structure at the interface between human and the BTENF. Once the finger contacts the BTENF, this capacitance structure can disrupt the original electrical field equilibrium of the BTENF, instantaneously triggering the sensing signal, which can be called the touch current (<10 ms). Notably, the strength of the current is closely related to the local enrichment capability of free ions within the human body, exhibiting biological specificity. In addition, similar to biological synapses, the BTENF also possesses spatiotemporal dynamic dependency and stimulation-strength perceptual properties. Based on this, by integrating a neural network, a visualization closed-loop biometric tactile encryption system has been fabricated, which can precisely analyze the biometric feature signals and physical feature signals of the touch current triggered by different users (accuracy>99.24%). As a proof of concept, a smart home with a biometric-level security encryption function is proposed, which can eliminate the risk of password leakage. Therefore, we believe that the BTENF provides a novel technological pathway for the smart home encryption field.

Keywords

Iontronic mechanism / Synapse-like micro-structure / Biological specificity / Smart home

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Funding

Key R&D Program of Shandong Province(2024CXGC010411)

National Key Research and Development Program(2022YFB3805802)

National Natural Science Foundation of China(52473307)

Taishan Scholar Program of Shandong Province in China(tsqn202211116)

Shandong Provincial Universities Youth Innovation Technology Plan Team(2023KJ223)

Natural Science Foundation of Shandong Province of China(ZR2023YQ037)

Shandong Province Science and Technology Small and Medium sized Enterprise Innovation Ability Enhancement Project(2023TSGC0344)

Natural Science Foundation of Qingdao(23-2-1-249-zyyd-jch)

China Postdoctoral Science Foundation(2024M761560)

Anhui Province Postdoctoral Researcher Research Activity Funding Project(2023B706)

Qingdao Key Technology Research and Industrialization Demonstration Projects(23-1-7-zdfn-2-hz)

Qingdao Postdoctoral Funding Project(QDBSH20240201011)

Suqian Key Research and Development Plan(H202310)

Systems Science Plus Joint Research Program of Qingdao University(XT2024202)

RIGHTS & PERMISSIONS

Donghua University, Shanghai, China