Graphene is a remarkable material: light, strong, transparent and electrically conductive. It can also convert heat to electricity. Researchers have recently exploited this thermoelectric property to create a new kind of radiation detector.
Classified as a bolometer, the new device has a fast response time and, unlike most other bolometers, works over a wide range of temperatures. With a simple design and relatively low cost, this device could be scaled up, enabling a wide range of commercial applications. Researchers describe a graphene-based radiation detector this week in Applied Physics Letters, from AIP Publishing.
The discovery of graphene in 2004 was anticipated to herald a whole new type of technology. “But unfortunately, there are some strong fundamental limitations for this material,” said Grigory Skoblin of Chalmers University of Technology in Sweden. “Nowadays, the real industrial applications of graphene are quite limited.”
Graphene—composed of single sheets of carbon atoms that form a flat, hexagonal lattice structure—has been used mainly for its mechanical properties.
“But our device shows that more fundamental properties can be used in actual applications,” Skoblin said. The new bolometer is based on graphene’s thermoelectric properties. Radiation heats part of the device, inducing electrons to move. The displaced electrons generate an electric field, which creates a voltage difference across the device. The change in voltage thus provides an essentially direct measurement of the radiation.
Read more: A new radiation detector made from graphene
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