Quantum tunnelling composite. Scanning electron micrograph (SEM). Quantum tunnelling composites (or QTCs) are composite materials of metals (green) an
Quantum tunnelling composite. Scanning electron micrograph (SEM). Quantum tunnelling composites (or QTCs) are composite materials of metals (green) and non-conducting elastomeric binder, used as pressure sensors. They use quantum tunnelling: without pressure, the conductive elements are too far apart to conduct electricity; when pressure is applied, they move closer and electrons can tunnel through the insulator. The effect is far more pronounced than would be expected from classical (non-quantum) effects alone, as classical electrical resistance is linear (proportional to distance), while quantum tunnelling is exponential with decreasing distance, allowing the resistance to change by a factor of up to 1012 between pressured and unpressured states. QTC can be used to make membrane switches like those used on mobile phones, pressure sensors and speed controllers. Magnification X 200 @10cm
Size: 4572px × 3932px
Photo credit: © STEVE GSCHMEISSNER/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: binder, cell, colored, coloured, composite, controllers, elastomeric, electrons, exponential, false, insulator, metal, mobile, phone, pressure, qtc, quantum, resistance, sem, sensors, speed, tunneling
