Research Papers in Physics and Astronomy


Date of this Version



Published in Physical Review Letters 100, 023002 (January 18, 2008). doi:10.1103/PhysRevLett.100.023002 Copyright © 2008 The American Physical Society. Used by permission. Online @


We image spatial distributions of Xeq+ ions in the focus of a laser beam of ultrashort, intense pulses in all three dimensions, with a resolution of ~3μm and ~12 μm in the two transverse directions. This allows for studying ionization processes without spatially averaging ion yields. Our in situ ion imaging is also useful to analyze focal intensity profiles and to investigate the transverse modal purity of tightly focused beams of complex light. As an example, the intensity profile of a Hermite-Gaussian beam mode HG1,0 recorded with ions is found to be in good agreement with optical images.

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