Lauren Fuge
Pioneering laser technology could be used to tame lightning and control where it strikes the ground, according to an international team of scientists.
Dry lightning strikes ignited many of the devastating bushfires of Australia’s 2019-20 “black summer”, but if we could artificially control the path and direction of lightning, fire risk could be drastically reduced.
A new laser tractor beam technology, described in a paper in the journal Nature Communications, may be the answer.
In a laboratory experiment, the team used a laser beam to trap and heat microparticles of graphene in the air between two metallic plates. This created a heated channel that induced lightning and allowed the electrical discharge to flow towards a pre-defined target.
“The experiment simulated similar atmospheric conditions to those found in real lightning,” says Vladlen Shvedov, co-author of the study from the Australian National University.
“We can imagine a future where this technology may induce electrical discharge from passing lightning, helping to guide it to safe targets and reduce the risk of catastrophic fires.”
This idea is not a new one: previous research has used laser beams to create atmospheric electrical breakdown, but these attempts required industry-scale infrastructure.
“This technique and subsequent manipulation of the discharge required enormous amount of laser intensity, limiting practical use because of restrictions on safety, control and precision,” says another co-author, physicist Andrey Miroshnichenko from UNSW Canberra.
In this study, however, adding microparticles to mix allowed the team to reduce the intensity of the laser beam by a thousand times, inducing lightning via a device with the size and output of a typical laser pointer.
“We have an invisible thread, a pen with which we can write light and control the electrical discharge to within about one tenth the width of a human hair,” says Miroshnichenko.
This, combined with the fact the discharge could be precisely controlled over long distances, means that future thunder-bolt trapping technology could be safe, accurate, and cheap.
But first, the research must be taken from the lab to the field.
“Our biggest challenge is not inducing the lightning from the environment but being able to capture and ground the charge in an effective and useful way,” Miroshnichenko explains.
“This will take some time to develop the required systems to handle such a large electrical charge. We believe that within five years we will have operational field stations and have full production within a decade.”
The team notes that this technology could also be used to finely-control electrical discharges in medicine and manufacturing applications.
“The medical applications include optical scalpels for the removal of hard cancerous tissue to non-invasive surgery techniques,” Miroshnichenko says.
“We are really at the start of learning what this completely new technology might mean.”