Class 3R Laser
| | Diamond provides 'new approach' to ultra-pure frequency lasers
A study by researchers at Macquarie University, based in Sydney, Australia, has found a new way to make ultra-pure frequency lasers based on diamond that avoids the problems responsible for destabilizing and broadening a laser’s output frequency. |
The results, published in the journal Optica, are expecteed to enable the next generation of lasers required for applications such as the remote sensing of greenhouse gases, powering atomic clocks and atom trapping, as well as in gravitational wave astronomy.
Using diamond, Dr Oliver Lux and Associate Professor Rich Mildren from the Department of Physics & Astronomy demonstrated stable single frequency operation using a simple laser cavity design that would normally be highly susceptible to destabilization. In particular, they placed the diamond at the midpoint of a long standing wave cavity, a configuration normally considered a ‘worst-case scenario’ for inducing the instabilities that cause polychromatic behavior to occur.
Potential for 'ultra-stability'
“Lasers are often thought of as being highly monochromatic, that is, of a single frequency, but in most cases their spectral purity is corrupted by a destabilizing effect referred to as spatial-hole burning. This effect causes the laser frequency to chaotically jump between a grouping of many closely spaced lines,” said Associate Professor Mildren.
“The problem is avoided in our case by using a light amplifying medium that relies on stimulated scattering rather than an excited medium that contains energy such as a population inversion.” Many laser applications require a pure frequency – a need made even more relevant by the current explosion in interest in gravitational wave astronomy, which relies on interference of single frequency laser beams that are high power and ultra-stable.
“Our finding provides greater freedoms for laser design and potentially much simpler, more robust systems. And, since the light amplifier ‘engine’ works using a fundamentally different principle to most lasers we are familiar with, a completely different range of materials may be used including those with extraordinary properties such as diamond. This promises a method of generating single frequency lasers over a wider choice of wavelengths and with potentially very high power.”
Read more at Diamond provides 'new approach' to ultra-pure frequency lasers
More on diamond lasers.
A team at Strathclyde University, Glasgow, Scotland, has developed a new type of high-performance, ultra-versatile Raman laser that harnesses diamonds to produce light beams with more power and a wider range of colors than current Raman lasers. |
Professor Martin Dawson, who initiated and oversaw the project at Strathclyde’s Institute of Photonics, commented, “Our new lasers can generate light ranging from the lower end of the ultra-violet part of the electromagnetic spectrum, right through the visible part, up to the middle of the infra-red region. That means they can plug many of the existing gaps in conventional lasers’ capabilities.”
The researchers add that the novel laser's capabilities could open up important new applications, such as better treatment of skin complaints and diabetes-related eye conditions, to improved pollution monitoring and aeronautical engineering. The research is being funded by the UK's Engineering and Physical Sciences Research Council (EPSRC).
Read more at http://optics.org/news/4/8/9
Last edited by steve001; 09-02-2016 at 10:35 PM.