Graphene used to create tiny "drums" with possible memory and sensor applications

Researchers from TU Delft developed very small graphene membranes (or "drums") that can be used to detect extremely small changes in position and forces. These tiny drums have find applications as sensors, and may also be used as memory chips in a quantum computer.

The researchers refer to these membranes as tiny drums, and they actually demonstrated how you can use microwave-frequency light to play on those drums. The membranes acts as a mirror in an optomechanical cavity. The microwave photos were shot on the drums which acts like a mirror. The researchers were able to sense minute changes in the position of the graphene sheet - even a change of 17 femtometers, nearly 1/10000th of the diameter of an atom.

Interestingly, the microwave light is not only used to detect the position of the drum, but it also pushes it a bit. That's how the researchers "played the drums". When the photos are converted to mechanical vibrations, they are "stored" in the drum for 10 milliseconds. It turns out that you can make the drumhead move both "up" and "down" and the same time - quantum superposition, which can be used as a quantum memory bit.

This is not the first "drum" reference in graphene research. In 2012, researchers from the University of Maryland and the NIST have shown that subjecting graphene to mechanical strain can mimic the effects of magnetic fields and create a quantum dot. The researchers fabricated graphene "drumheads" by suspending graphene over shallow holes in a substrate of silicon dioxide. 

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Posted: Aug 26,2014 by Ron Mertens