title: Generation of doughnut laser beams by use of a liquid-crystal cell with a conversion efficiency near 100%.
abstract: We present a novel technique for producing a doughnut laser beam by use of a liquid-crystal cell. It is demonstrated that the liquid-crystal cell exhibits an efficiency in energy conversion near 100%. One of the main advantages of this method is its capability of dynamic switching between a Gaussian mode and a doughnut mode of different topological charges. The liquid-crystal cell is also dynamically tunable over the visible and near-infrared wavelength range. These advantages make the device appealing for laser trapping methods used in single-molecule biomechanics and for optical guiding of cold atoms.
authors.forename: Djenan
authors.initials: D
authors.lastname: Ganic
authors.forename: Xiaosong
authors.initials: X
authors.lastname: Gan
authors.forename: Min
authors.initials: M
authors.lastname: Gu
authors.forename: Mathias
authors.initials: M
authors.lastname: Hain
authors.forename: Somakanthan
authors.initials: S
authors.lastname: Somalingam
authors.forename: Svetomir
authors.initials: S
authors.lastname: Stankovic
authors.forename: Theo
authors.initials: T
authors.lastname: Tschudi