Published April 16, 2009
Scientists have found a way to bend lasers — and may use it to bend lightning as well.
A team led by Pavel Polynkin of the University of Arizona sent a special sort of laser beam — pulsed instead of steady, and asymmetrical so that one edge was brighter than the other — through a series of filters.
They found that the beam actually curved a bit, by about 5 millimeters (about 1/5 of an inch) over the total distance of 60 centimeters (2 feet).
"People expect lasers to do certain things, like propagate in a straight line," Polynkin told Scientific American. "The fact that a laser beam actually curves is quite unusual."
Since the laser pulses are so intense, they zap the air they pass though, leaving behind an ionized plasma trail. That trail might be conductive enough to form a natural pathway for lightning to travel along, points out Jérôme Kasparian at the University of Geneva.
Kasparian, who's been trying to coax lightning from thunderclouds using straight plasma beams, thinks Polynkin's curved beams could be used to divert lightning toward or away from specific targets.
"It would be fun to see curved lightning discharges," he told New Scientist.
Polynkin's teams' study was published in the April 10 issue of Science.