Research objectives and content
Periodically-poled lithium niobate (PPLN) is emerging very rapidly as a nonlinear optical material of great versatility and great strategic importance. It offers the possibility of very efficient optical frequency conversion, via harmonic generation and optical parametric oscillation (OPO), across the whole of its transmission range, from 0.35 pim to 5pim. Thus the development of compact coherent light sources operating anywhere within this important spectral range is now possible. A particularly attractive possibility, exploiting the large nonlinearity of this material is that widely tunable OPO devices, driven directly by a pulsed semiconductor laser, should now be realisable using PPLN, thus leading to very compact devices, potentially of very low cost. The specific goal of this research will be to develop such a device, working at the Optoelectronics Research Centre, which has a leading capability in the fabrication of PPLN material and in OPO devices using PPLN. Training content (objective, benefit and expected impact)
This work will provide an excellent training in the stimulating environment of one of Europe's leading laser laboratories. I will gain new experience in (1) the use of picosecond semiconductor lasers (2) in developing an improved understanding of the behaviour of OPOs. These important devices are less well understood than lasers, and deeper understanding will lead to improved performance and applicability. Links with industry / industrial relevance (22)
The ORC already has good contacts, both with Thomson CSF and GEC over the exploitation of PPLN OPOs. These contacts will be strengthened through this work, particularly as the compact, low-cost,
semiconductor-laser-pumped OPO will enhance the prospects of widespread industrial application, in areas such as remote sensing, process control etc.