Laser controls ultra-fast liquid switch for terahertz radiation

Researchers at Ruhr University Bochum, Germany, have developed an ultra-fast water-based switch. A short but powerful laser pulse converts the water into a conductive state within less than a trillionth of a second (10-12 seconds), during which time it behaves almost like a metal. This makes it faster than the fastest known switching speed of a semiconductor to date.