Scientists have figured out a way to perfectly beam energy across any room, thanks to a sci-fi like device they call an “anti-laser.”
The idea is simple: Just like a laser emits light particles, or photons, one after another in a neat and orderly row, an anti-laser sucks up photons one after another in reverse order. Researchers have long speculated that a device like this might make wires and charging cables a thing of the past, allowing people to beam energy invisibly across a room to a laptop or phone and power it without plugging it in. But though basic anti-lasers have been tested before, the real world isn’t as neat and orderly as a laser pointed at a fixed receiver in a laboratory. Electronics move around, objects get in the way, walls reflect energy in unexpected ways. The new anti-laser demonstrated in this experiment accounts for all that, and it receives scattered energy beamed around a space in an unpredictable pattern — still receiving 99.996% of the sent power.
The formal term for the method they used is “coherent perfect absorption” (CPA). CPA uses one machine to send power across the room, and another (the “anti-laser”) to suck it back up. Past CPA experiments, the researchers wrote in a paper published Nov. 17 in the journal Nature Communications, were exciting but had a fundamental limitation: the direction of time. The experiments worked only in situations where time could flow as easily backward as forward, which rarely exist in our day-to-day lives.
TechDial 