title: Rotational control within optical tweezers by use of a rotating aperture.
abstract: We demonstrate a simplified method of rotational control of objects trapped within optical tweezers that does not require high-order modes, interferometric precision, or computer-controlled optical modulators. Inserting a rectangular aperture into the optical beam results in a focused spot that also has rectangular symmetry. We show that an asymmetric object trapped in the beam has its angular orientation fixed such that rotation of the aperture results in a direct rotation of the particle.
authors.forename: Anna T
authors.initials: AT
authors.lastname: O'Neil
authors.forename: Miles J
authors.initials: MJ
authors.lastname: Padgett