Supercontinuum

A supercontinuum or not entirely white laser light is the term used to describe laser light which, due to its passage through a non-linear optical medium, has an extremely broad optical spectrum . While the laser light is relatively narrow-band, a supercontinuum can span a frequency range of more than an octave .

Supercontinua can arise through the use of non-linear effects when laser beams are passed through glass fibers at high intensities, but focusing in air is sufficient for this. In most cases, intense light pulses from femtosecond lasers are used . But the use of pulses with significantly longer durations can also show the desired broadening. Continuous laser operation ( cw ) is even possible in long fibers . The physical mechanisms involved and the spectral structure of the supercontinua are quite different depending on the pulse duration, dispersion and length of the fiber, etc. The formation of supercontinua is now relatively well understood and can be reproduced with computer simulations.

There are many possible uses of supercontinuum laser sources. So they are z. B. used as a light source in (confocal) microscopy and spectroscopy , for optical coherence tomography and for the implementation of frequency combs.

Web links

• Supercontinuum generation in the Encyclopedia of Laser Physics and Technology (Engl.)

See also

• Kerr effect
• Self phase modulation
• Spectral analysis

swell

1. ↑ Spectrum of Science: White Laser Light , March 2007 edition.
2. ^ Govind Agrawal: Nonlinear Fiber Optics . 4th edition. Academic Press, 2006, ISBN 0-12-369516-3 .
3. ↑ Dominik Wildanger, Eva Rittweger, Lars Kastrup, Stefan W. Hell: STED microscopy with a supercontinuum laser source . In: Optics Express . tape 16 , no. 13 , 23 June 2008, p. 9614-9621 , doi : 10.1364 / OE.16.009614 .