Development of Graphene Light Detector Could Lead to Heat Vision Contacts

Posted on March 19, 2014

Heat vision contacts may soon become a reality. Researchers at the University of Michigan have developed a tiny graphene light detector that can sense the full infrared spectrum. The researchers say in a release that this "has the potential to put heat vision technology into a contact lens."

Zhaohui Zhong, assistant professor of electrical and computer engineering, says in a statement, "We can make the entire design super-thin. It can be stacked on a contact lens or integrated with a cell phone."

The current generation of graphene-based detectors have poor sensitivity. The University of Michigan researchers worked with graduate students to design a new way of generating the electrical signal. The researchers put an insulating barrier layer between two graphene sheets. The bottom layer had a current running through it. When light hits the top layer, it frees electrons, creating positively charged holes. The electrons slip through the barrier and into the bottom layer of graphene using a "quantum mechanical trick." The positively charged holes, left behind in the top layer, produce an electric field that affects the flow of electricity through the bottom layer. By measuring the change in current, the researchers were able to deduce the brightness of the light hitting the graphene. The researchers say the device is already smaller than a pinky nail and could easily be scaled down.

IEEE Spectrum reports that in addition to infrared contacts the new technology could also be used to create medical applications the let doctors monitor blood flow.

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