Improved generation of ultra-short laser pulses
Attosecond optical pulse generation is revolutionising physics and chemistry in laboratories around the world. It enables probe spectroscopy to view molecular motion and electron transfer between atoms. High harmonic generation is a common way to convert a laser source of lower frequency into higher frequencies to achieve very fast pulses. The technology is a highly non-linear optical process with exciting potential for molecular imaging and compact generation of X-rays for bio- and nano-imaging. However, conversion efficiency relating the produced intensity to the input intensity is relatively low, largely due to de-phasing or poor phase matching of the non-linear conversion process.EU-funded scientists enhanced the conversion efficiency of high harmonic generation through two different approaches to quasi-phase matching within the scope of the project ATTOSECOND OPTICS. Sharp sawtooth grating-assisted phase matching exhibited conversion equivalent to conventional phase matching and closely approaching the ideal case. Secondly, the team also developed ways to control the spectral, temporal and spatial characteristics of the attosecond pulses and the polarisation properties of the produced beam. Scientists are currently developing a novel device based on the high harmonic generation technology.The ability to produce attosecond pulses of high intensity by increasing conversion efficiency has been long sought. ATTOSECOND OPTICS has achieved this, paving the way to high-performance table-top X-rays and other imaging and analysis devices.
