Zakery, A.Ruan, Y.Rode, A.Samoc, M.Luther-Davies, B.2007-07-052007-07-052003Journal of the Optical Society of America B: Optical Physics, 2003; 20(9):1844-18520740-32241520-8540http://hdl.handle.net/2440/34943This paper was published in Journal of the Optical Society of America B and is made available as an electronic reprint with the permission of OSA. The paper can be found at the following URL on the OSA website: http://www.opticsinfobase.org/abstract.cfm?URI=josab-20-9-1844. Systematic or multiple reproduction or distribution to multiple locations via electronic or other means is prohibited and is subject to penalties under law.enCopyright © 2003 Optical Society of AmericaJournal article002006447110.1364/JOSAB.20.0018440001851820000072-s2.0-014152632850281