title: Ultrasmall bullets of light--focusing few-cycle light pulses to the diffraction limit.
abstract: We demonstrate an essentially dispersion-free and diffraction-limited focusing of few-cycle laser pulses through all-reflective microscope objectives. By transmitting 6-fs-pulses from a Ti:sapphire oscillator through an all-reflective 0.5 NA objective, we reach a focus with a beam diameter of 1.0 µm, preserving the time structure of the pulses. The temporal and spatial pulse profile is recorded simultaneously using a novel tip-enhanced electron emission autocorrelator, indicating a focal volume of these pulses of only 1.8 µm3. We anticipate that the demonstrated technique is of considerable interest for inducing and probing optical nonlinearities of individual nanostructures.
authors.affiliation: Institut für Physik, Carl von Ossietzky Universität, D-26111 Oldenburg, Germany. b.piglosiewicz@uni-oldenburg.de
authors.forename: B
authors.initials: B
authors.lastname: Piglosiewicz
authors.forename: D
authors.initials: D
authors.lastname: Sadiq
authors.forename: M
authors.initials: M
authors.lastname: Mascheck
authors.forename: S
authors.initials: S
authors.lastname: Schmidt
authors.forename: M
authors.initials: M
authors.lastname: Silies
authors.forename: P
authors.initials: P
authors.lastname: Vasa
authors.forename: C
authors.initials: C
authors.lastname: Lienau