Phys. Rev. Lett. 103, 024501 (2009)

A millimetre-sized water droplet sitting on a vibrating crystal surface can be forced to form a narrow column more than a centimetre long.

Leslie Yeo and his colleagues at Monash University in Clayton, Australia, created controllable, nozzle-free liquid jets by focusing energy into the water from surface acoustic waves (SAWs): earthquake-like vibrations generated electrically in the underlying crystal.

SAW devices are powerful — a wave 10 nanometres in amplitude can generate surface accelerations 10 million times that of gravity — and inexpensive, already inhabiting most mobile phones. Researchers hope to use them to manipulate fluids at the microscale. They can make liquid drops wobble, slide sideways and break up into a fine mist.