By Gary Thomas Scientists at TU Darmstadt in conjunction with
their partners in the European Union’s ‘Subtune’ project have
devised semiconductor lasers that emit light over a broad
spectral range of 100 nm. This is the first ever single
semiconductor laser with such capability. These new lasers
herald the development of gas sensors with high responsiveness
and fiber optic telecommunication networks that are economical
and efficient. Light emitted from surface emitting semiconductor
lasers are perpendicular to the wafer plane on which the lasers
are fabricated. They are employed as light sources in devices
like laser printers and computer mice since they do not consume
much power. The work carried out at the Institute for Microwave
Technology and Photonics at TU Darmstadt has enhanced the
operable range of these lasers. The scientists leveraged a
characteristic of surface emitting lasers, namely, their high
resonator length to emitting area ratio which causes emitted
wavelengths to be spaced further apart. Th