'Saser' claimed as next step for laser

Scientists at Nottingham University, in collaboration with colleagues at the Lashkarev Institute of Semiconductor Physics in the Ukraine, have produced the saser, a sonic equivalent to the laser.

In operation, the saser device is comprised of a man-made structure called a ‘superlattice’, composed of around 50 sheets of two alternating layers of gallium arsenide and aluminium arsenide, semiconductor materials just a few atoms thick.

In an interview with The Engineer Online, Prof Anthony Kent, from the university’s school of physics and astronomy, explained that a light beam can be used to excite electrons in these semiconductor materials into a high energy state, energy they can then lose through the process of phonon emission.

‘What happens in our saser is similar to the way a laser works: a few excited electrons relax and lose their energy and momentum spontaneously through the emission of a phonon.