Researchers from the Universities of Bath and Exeter have developed and demonstrated an optical switch made from graphene. this switch has an incredibly short optical response - nearly a hundred times quicker than current materials.
This fast response is in the infrared part of the electromagnetic spectrum, which makes it useful for telecommunications, security and also medicine applications. Current optical switches have as response rate of a few picoseconds, and the few-layer-graphene switch's response rate is about one hundred femtoseconds.
The researchers hope that this research may lead to the development of graphene-based quantum cascade lasers. Quantum cascade lasers are semiconductor lasers used in pollution monitoring, security and spectroscopy, and few-layer graphene could emerge as a unique platform to enable them.
Only a few months ago, researchers from University of Exeter have developed a new flexible, transparent and ultra-lightweight photodetector device made from graphene and graphExeter (a room-temperature transparent conductor discovered at the University of Exeter in 2012). I don't know if the current research uses graphExeter as well (they only mention they use "few-layer graphene").