Dublin City University. School of Physical Sciences
Abstract
A dedicated laboratory has been built in DCU to study the interaction between ultra-short, intense laser radiation with both solid and gaseous materials. A commercial laser system with high intensity (3 mJ), and short temporal dura- tion ( 32 fs) has been installed and characterised as part of this project. A static, single shot Nomarski interferometer has been developed and by exploiting the non- linear response of an optical filter, the pulse width of the laser has been measured.
The interaction of high intensity laser radiation with solid materials was also investigated. Experiments using a wire probe to characterise a silicon laser produced plasma were performed. The emission of ions and electrons within the laser plasma as well as the angular distribution of both species has been measured and the effects of laser intensity, laser wavelength and laser polarisation are investigated. In a complementary experiment, the expansion dynamics of the laser plasma are studied with space resolved Langmuir probe measurements. These results are analysed and presented in the context of double layer formations within the plasma plume.
A Wiley-McLaren spectrometer has been built to study the interaction of high intensity laser light with gas jets. The design and construction of the spectrometer is detailed as well as its characterisation. The effects of polarisation are studied with molecular nitrogen as a gas target