Quantum tunnelling composite. Scanning electron micrograph (SEM). Quantum tunnelling composites (or QTCs) are composite materials of metals ( blue) 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 | |
Licence : | Droits gérés |
Crédit: | Science Photo Library / Gschmeissner, Steve |
Taille de l’image : | 4572 px × 3932 px |
Model Release : | Non requis |
Restrictions : | - |