Photons Ride Optomechanical ‘Seesaw’

A nanoscale “seesaw” that shuttles photons back and forth could present an optomechanical alternative for computing and sensing applications.

On either side of the seesaw are photonic crystal cavities to capture photons. Optical forces generated by the captured photons caused the seesaw to move up and down.

“When we filled the cavity on the left side with photons and leave the cavity on the right side empty, the force generated by the photons started to oscillate the seesaw,” said University of Minnesota professor Dr. Mo Li, whose team developed the device. “When the oscillation was strong enough, the photons can spill over along the beam from the filled cavity to the empty cavity during each cycle.”

The stronger the oscillation, the more photons are shuttled to the other side. The team has been able to transport approximately 1000 photons in a cycle.

“The ability to mechanically control photon movement as opposed to controlling them with expensive and cumbersome optoelectronic devices could represent a significant advance in technology,” said graduate student Huan Li.

The technique could find uses in accelerometers or gyroscopes for navigation, as well as in photonic circuits, the researchers said.

The work was funded by the U.S. Air Force Office of Scientific Research.

The research was published in Nature Nanotechnology (doi:10.1038/nnano.2014.200).

For more information, visit www.umn.edu.