Showing papers by "David McGloin published in 2003"
TL;DR: The radial dependence of the observations of the spinning and orbital motion of a microscopic particle trapped within a multiringed light beam is found to be in close agreement with the accepted theory.
Abstract: We observe the spinning and orbital motion of a microscopic particle trapped within a multiringed light beam that arises from the transfer of the spin and orbital components of the light's angular momentum. The two rotation rates are measured as a function of the distance between the particle and the axis of the trapping beam. The radial dependence of these observations is found to be in close agreement with the accepted theory.
338 citations
TL;DR: The self-healing properties of interfering Bessel beams allow the simultaneous manipulation and rotation of particles in spatially separated sample cells in optical tweezers and rotators.
Abstract: We examine the properties of interfering high-order Bessel beams. We implement an experimental setup that allows us to realize these interferograms, using interfering Laguerre-Gaussian beams and an axicon. We demonstrate the use of such beams for controlled rotation of microscopic particles in optical tweezers and rotators. The self-healing properties of interfering Bessel beams allow the simultaneous manipulation and rotation of particles in spatially separated sample cells.
196 citations
TL;DR: It is shown that SLMs may be used to generate a wide variety of optical potentials that are useful for the guiding and dipole trapping of atoms by the production of a number of different light potentials using a single SLM device.
Abstract: We discuss the application of spatial light modulators (SLMs) to the field of atom optics. We show that SLMs may be used to generate a wide variety of optical potentials that are useful for the guiding and dipole trapping of atoms. This functionality is demonstrated by the production of a number of different light potentials using a single SLM device. These include Mach-Zender interferometer patterns and the generation of a bottle-beam. We also discuss the current limitations in SLM technology with regard to the generation of both static and dynamically deformed potentials and their use in atom optics.
174 citations
TL;DR: This work demonstrates the use of a spatial light modulator (SLM) to facilitate the trapping of particles in three-dimensional structures through time-sharing and discusses limiting factors inherent in current phase only SLM design for applications in both optical tweezing and atom trapping.
Abstract: We demonstrate the use of a spatial light modulator (SLM) to facilitate the trapping of particles in three-dimensional structures through time-sharing. This method allows particles to be held in complex, three-dimensional configurations using cycling of simple holograms. Importantly, we discuss limiting factors inherent in current phase only SLM design for applications in both optical tweezing and atom trapping.
103 citations
TL;DR: In this article, the authors demonstrate the production of an optical beam with a number of embedded optical bottles by passing a Laguerre-Gaussian beam, with a radial mode index of p>1, through an axicon.
102 citations
TL;DR: In this paper, the authors examined coherent effects in a four-level Vee scheme and showed that the system can be made to display a number of different phenomena, including the inhibition of two-photon absorption and the production of multiple dark states.
Abstract: We examine coherent effects in a four-level Vee scheme. We show that the system can be made to display a number of different phenomena, including the inhibition of two-photon absorption and the production of multiple dark states. We show that this latter effect is due to the independent control of the Autler–Townes splitting of the upper and lower probe field by independent driving fields. We suggest possible experimental systems in rubidium for the observation of such effects.
46 citations
TL;DR: In this paper, a low velocity intense source (LVIS) of cold rubidium atoms is guided along a co-propagating far-off resonance light guide, and an 8% enhancement of the guided atomic flux is observed in the steady state.
Abstract: A low velocity intense source (LVIS) of cold rubidium atoms is guided along a co-propagating far-off resonance light guide. An 8% enhancement of the guided atomic flux is observed in the steady state. Data are presented for the transient response of the LVIS to the guide beam observing a non-adiabatic kick and a transient 25% enhancement of the guided flux. A characteristic decay time of 0.45 s is recorded for the return to the steady state flux.
7 citations
TL;DR: In this paper, the simultaneous spinning and orbital motion of a microscopic particle trapped off-axis in a high-order Bessel beam was observed, and the spin and orbital angular momentum content of the light beam acting on the particle were reported.
Abstract: We observe the simultaneous spinning and orbital motion of a microscopic particle trapped off-axis in a high-order Bessel beam. Quantitative measurements relating the spin and orbital angular momentum content of the light beam acting on the particle are reported. Experimental results were in agreement with the theory.
1 citations
TL;DR: In this paper, the reconstruction properties of Bessel beams have been used for optical manipulation of particles simultaneously over 1 cm using the reconstruction property of the Bessel beam and their use for controlled rotation of particles.
Abstract: We demonstrate optical manipulation of particles simultaneously over ~1cm using the reconstruction properties of Bessel beams. We also demonstrate the production of interfering Bessel beams, and their use for controlled rotation of particles.
22 Jun 2003
TL;DR: In this article, the authors demonstrate the use of Bessel beams to trap and manipulate biological specimens in completely separate sample chambers, separated by distances that preclude trapping with a Gaussian beam.
Abstract: Bessel beams can be used as optical tweezers, to trap and manipulate small particles, including biological specimens. Here we demonstrate the use of such beams to trap and manipulate particles simultaneously that may reside in completely separate sample chambers, separated by distances that preclude trapping with a Gaussian beam. This also demonstrates another property of the Bessel beam, in that since it is a set of rings it can trap both low and high refractive index particles. The distance behind the particle that the Bessel beam reconstructs is dependent on the properties of the particle, and this may be useful in cell characterisation. We also demonstrate the generation of more complex patterns of nondiffracting light beams, by using interfering Bessel beams. We generate these by using a Mach-Zender interferometer in which each of the arms has a Laguerre-Gaussian beam of differing handedness.