Researchers at Ruhr University Bochum, Germany, have developed a new concept for switches with an unprecedented speed that becomes conductive thousands of times faster than current state-of-art semiconductor-based switches. Such switches are used in computers, smartphones, and wireless communications.
Essentially, 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.
To create the switch, researchers used a highly concentrated sodium iodide dissolved water- in simpler terms, salty water. And sprayed this salty water from a custom-made nozzle as a thin sheet only a few microns thick. The water jet was excited with a short but powerful laser pulse at 400 nanometers (nm). This bumps electrons out of the dissolved salts, increasing the conductivity of water. Since the laser pulse is so fast, the water becomes conductive and behaves almost like a metal.
All of this happens in less than one trillionth of a second, which translates to potential computer speeds in the terahertz (THz) range, making this water-based switch faster than the fastest semiconductor switching speed currently known. A second laser reads back the state of the water.
Researchers hope the findings will lead to new research avenues and water-based technologies. Terahertz devices could someday enable much faster computing, and water-based technology could offer a more environmentally friendly alternative to rare-earth metals.
Source: APL Photonic / Interesting Engineering