Of the many different types of laser the semiconductor laser represents the most numerous; both in terms of numbers sold each year and range of applications. In comparison with other types of lasers, semiconductor lasers are small, efficiently convert electrical energy into light energy, have very long operating lifetimes and can be switched on and off (modulated) at extremely high rates. By using different semiconductor systems and different structures it is possible to produce laser emission from the near UV (~400nm) to the THz region (> 100μm). These properties makes semiconductor lasers very well suited for applications including data storage, data projectors, optical communications systems, printing and medical treatments and imaging. Sales of semiconductor lasers in 2012 are estimated to be $3.8 billion.
The main areas of current research include increasing the range of emission wavelengths, both into the uv and also the far infrared, and further improving the efficiency, coupled with improved temperature stability (a significant disadvantage of semiconductor lasers is that their operating current increases rapidly with increasing temperature).
In Sheffield we are developing Quantum Cascade Lasers which operate in the infrared spectral region for applications that include extremely sensitive gas-type specific sensing and Quantum Dot Lasers for increased temperature stability devices and also devices that can be directed integrated with silicon electronics.
Related Research Projects:
- Quantum Cascade Lasers
- Quantum Dot Lasers