Quantized Channels and Instability Modulation Strategy in Au/PDMS Single-Crack Evolution.

Area of Science:

• Materials Science
• Nanotechnology
• Physics

Background:

• Crack-based sensors are vital for microdeformation detection but suffer from unstable performance due to disordered crack networks.
• Precisely analyzing single-crack contributions to sensing is challenging with conventional designs.

Purpose of the Study:

• To develop a controllable single-crack architecture for stable and ultrasensitive microdeformation detection.
• To investigate the conductive channel evolution and conduction mechanisms in engineered crack networks.
• To enhance sensor performance through hybrid nanoengineering strategies.

Main Methods:

• Fabrication of Au/PDMS films with a stress-engineered single-crack architecture.
• High-resolution in situ monitoring of crack evolution and conductive channel behavior.
• Integration of single-walled carbon nanotubes as crack-bridging networks.

Main Results:

• Identified three distinct regimes of conductive channel evolution: nonpenetrating crack initiation, metal point contact, and fully penetrated fracture.
• Observed strain-quantized conductance with reproducible quantum steps (multiples of 2e²/h) in the metal point contact regime, indicating ballistic transport.
• Demonstrated stable resistance changes (ΔR/R₀ ≈ 10⁶) at 2.45% strain using carbon nanotube crack-bridging networks, overcoming instability in fully penetrated fractures.

Conclusions:

• The proposed single-crack architecture enables controllable conductive channels for stable microdeformation sensing.
• Coupled quantum-classical conduction mechanisms and hybrid nanoengineering offer a new paradigm for ultrasensitive epidermal electronics.
• This approach paves the way for advanced AI-enhanced biomedical diagnostics.