title: On the concept of "tractor beams".
abstract: We demonstrate the existence of a class of optical beams where the nonconservative forces can be locally oriented in a direction opposite to the propagation wave vector. Objects placed in the vicinity of these locations will move toward the source of light. The behavior of these negative forces is discussed for the particular case of nondiffracting rotating scale-invariant vector electromagnetic waves.
authors.affiliation: CREOL, The College of Optics and Photonics, University of Central Florida, Orlando, Florida 32816-2700, USA.
authors.forename: S
authors.initials: S
authors.lastname: Sukhov
authors.forename: A
authors.initials: A
authors.lastname: Dogariu