title: Deterministic approach to the generation of modified helical beams for optical manipulation.
abstract: We present a deterministic method to generate modified helical beams which create optical vortices with desired dark core intensity patterns in the far-field. The experiments are implemented and verified by a spatial light modulator (SLM), which imprints a phase function onto the incident wavefront of a TEM00 laser mode to transform the incident beam into a modified helical beam. The phase function can be calculated once a specific dark core shape of an optical vortex is required. The modified helical beam is exploited in optical manipulation with verification of its orbital angular momentum experimentally.
authors.forename: J
authors.initials: J
authors.lastname: Lin
authors.forename: X-C
authors.initials: XC
authors.lastname: Yuan
authors.forename: S H
authors.initials: SH
authors.lastname: Tao
authors.forename: X
authors.initials: X
authors.lastname: Peng
authors.forename: H B
authors.initials: HB
authors.lastname: Niu