A time-stamping tactile sensor enabled by pseudoconductive interface design at dielectric heterojunctions

Capturing the spatiotemporal aspects of tactile stimuli is essential for real-time and intelligent operation in emerging human-machine interfaces, electronic skin, and neuromorphic systems. However, most time-resolved tactile sensors rely on complex architectures involving conductive components, active switching elements, or external circuitry, limiting their flexibility and energy efficiency. Here, we introduce a time-stamping tactile sensing strategy on the basis of mechanical stimulus-driven pseudoconductive (MSPC) channels that form at dielectric heterojunctions. Comprehensive band-structure analysis of combinations among 11 dielectric materials reveals that MSPC channels arise from band alignment governed by Fermi-level shifts, quasi-Fermi formation, and field-induced band tilting. The MSPC favorability index is devised to quantitatively predict optimal combinations across 72 dielectric heterojunctions. Mechanical charging activates dielectric pathways that transmit mechanoelectric signals over extended distances, achieving an 854% enhancement across 129 millimeters. A proof-of-concept time-stamping tactile sensor leverages the time-dependent deactivation dynamics of MSPC channels to intrinsically encode spatial and temporal information, offering a passive, scalable, and energy-efficient route for next-generation tactile perception.