Tiny lasers can be made from soap bubbles

Soap bubbles can be turned into lasers that are exceptionally good at sensing electric fields and pressure.

“To get lasing, almost any bubble is fine. We’ve used regular hand soaps or a mixture that you can buy for children. You just need to put a small amount of fluorescent dye inside, and it works perfectly,” says Matjaž Humar at the Jožef Stefan Institute in Slovenia, who produced the bubble lasers with Zala Korenjak, also at the Jožef Stefan Institute .

Lasers require three key components. The first is a cavity in which light can bounce back…