ORC Seminar Series

Speaker: Professor J.R.Taylor

Femtosecond Optics Group, Imperial College

Date: Wednesday 10th September 2008
Time: 2pm
Venue: Lecture Theatre J, Building 2

Abstract:

The high power fibre laser in its many and varied formats, integrated with a non linear optical fibre provides a versatile source of radiation that has been both a scientific and commercial success. Although the underlying physics of the processes utilized in these devices has been well established for twenty-plus years, it has been the dramatic steps forward in technology and the control of the nonlinearity that has led to the rapid uptake of these integrated devices. In addition to the fibre laser, it clearly has been the introduction of the photonic crystal fibre that has been a strong influence on the particular success of the supercontinuum source. The flexibility of the waveguide dispersion and the ability to place the zero dispersion at effectively any wavelength allows matching of pump source to fibre, while the ability to enhance or to effectively eliminate the nonlinearity has uniquely placed the PCF as an indispensable element in the control of non linear optical processes. Accompanied by improved modelling techniques permitting excellent agreement between theory and experiment, improved fibre geometries have been suggested and introduced, some of which will be described here, to allow wavelength extension and power scaling of supercontinuum sources. The power scaling of cw pumped supercontinua will  be described , achieving in excess of 100mW/nm in the infrared and also to be reported is the observation of short wavelength extension in 1mm cw pumped systems to 600nm where up to 2mW/nm has been measured. Techniques to extend the short wavelength extent will be described.