Pushing lasers well beyond the limits - novel laser sources

Types of lasers

Gas lasers use a gas as the active medium. There are a variety of gas lasers. The most common are Helium-Neon (HeNe) ones, which have a primary output of visible red light and are widely used for alignment purposes and in the bio-medical field. Carbon-Dioxide (CO₂) lasers emit energy in the far-infrared (~10 µm), and are used for cutting hard materials, while excimer lasers emit light in the ultra-violet spectrum and are used in applications where small structures are important, e.g. for micromachining and lithography.

Dye lasers use complex organic dyes, such as rhodamine 6G, in liquid solution or suspension as lasing media. They are tuneable over a broad range of wavelengths. Uses include spectroscopy, which pertains to the dispersion of an object's light into its component colours (i.e. energies). This would be used, for example, in the study of biological material.

Semiconductor lasers, sometimes called diode lasers, are electronic devices; the low powered versions of which are used in an array of appliances such as laser pointers and CD players. There are, however, very high power types of lasers. Applications of these are abundant in science, industry, and the medical and military fields.

The CSIR’s laser systems group designs efficient and high power diode-pumped solid-state laser systems (2 µm). These researchers use both experimental work and mathematical models to push these lasers well beyond the limits of currently-available technology. The main focus of the research is on mid-infrared power diode-pumped solid-state laser systems. Mid-infrared lasers are popular because they are far less harmful to the eye compared to lasers operating in the visible or near-infrared spectral region. In addition, many characteristic molecular absorption lines are in this region; making these lasers useful for chemical spectroscopy, laser remote sensing of pollution, and medical applications