In a recent development, Berkeley engineers have fabricated a new type of semiconductor laser that successfully completes an elusive task in the field of optics: the capacity to maintain a single mode of discharged light and at the same time keep the ability to scale up in power and size.
The development is an achievement implying size does not have to be achieved at the expense of coherence thereby enabling lasers to have great power and to cover greater distances for many applications.
A team of researchers at Berkeley demonstrated that a semiconductor membrane with same-size and evenly spaced perforations functions as a perfect scalable laser chamber. They demonstrated that laser discharges a consistent single wavelength irrespective of the size of the cavity.
The invention appears in a study published in the journal Nature.
In fact, to increase the power size as well as size of a single-mode laser has been challenging in the field optics since the construction of first laser in 1960. After six decades, Berkeley researchers have demonstrated it is possible to include both these qualities in a laser.
The publication is the most important from the group till date, stated the lead author.
Meanwhile, despite the vast range of applications initiated by the invention of laser from surgical tools to precision etching to barcode scanners, researchers in optics have had to contend with their persistent limit.
Thus, with the increase in size of the laser cavity, the coherent single-wavelength directed light that is a defining feature of a laser starts to disintegrate as the size of the laser cavity elevates.
On the other hand, the standard method is to use external mechanisms, such as waveguide, to expand the beam.