Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Experimental studies of cold atom guiding using hollow light beams

D. P. Rhodes

Published Jan 1, 2005• 0 citations
OpenAlex

Abstract

This thesis is concerned with the guiding of cold atoms using optical forces, which is of great importance in the field of atom optics. Atomic beams can be used for precision sensor equipment, building nano-scale structures, construction of quantum computers and to further the understanding of the properties of atoms. Atoms are guided along light beams using the dipole force; there are two regimes under which this force works. Typically red-detuned guides are used (atoms are attracted towards the light) such guides, however, require large detuning and high powers. In this thesis we investigate the use of blue-detuned (atoms are repelled from the light) hollow light beams of moderate power (a few hundred mW) and confine atoms in the dark centre of the beams. Several magneto-optical traps (MOTs) have been constructed to exploit different guiding geometries. Hollow beams have been generated using a variety of methods; in particular the use of a computer controlled spatial light modulator (SLM) has provided great versatility and simplicity to the experimental arrangements. First, experiments were performed with a low-velocity intense source (LVIS) of atoms. A co-linear LG beam significantly enhances the observed flux, however, considerable difficulties are encountered loading atoms into oblique guides. Imaging a hole in the walls of the light tube was used to improve the loading efficiency. Second, guiding a free-falling atom cloud is performed using a non-diffracting Bessel beam. It is found that while the potential of the Bessel beam is steeper than equivalent LG beams the power distribution across the beam severely limits its usefulness. The next study investigated higher-order LG guide beams generated with an SLM. High order modes have a narrower profile so confine the atoms with less interaction with the guide beam, leading to a more natural guide (as opposed to a pushing force). Finally the SLM was used to create non-trivial beam shapes for beam splitters and interferometers.

Related papers

Hollow Bessel Tunnel Guide: Theory and Experiment

Narupon Chattrapiban

The main objectives of this thesis were to create and investigate properties and applications of all-optical atomic guides, which are potential building blocks for atom optics experiments. Specifically, we investigated experimentally and theoretically the evolution of the transverse and longitudinal atomic distributions in blue-detuned Bessel tunnels. These tunnels provide confining potentials that are comparable to or higher than the average kinetic energy of cold hundreds of microKelvin) ensembles. The new work highlighted in this thesis include investigations of the following: 1) the generation of Bessel beams using a 2D spatial light modulator (SLM) (both experimental measurement and numerical simulations were performed), 2) the efficiency of the SLM for converting light from a Gaussian beam to a Bessel beam, 3) the behavior of several propagating structures that might be useful for guiding atoms, 4) the atom-tunnel dynamics, 5) an atom switch and delay line (along with measurements of the switch efficiency), and 6) the single-mode propagation in an idealized tunnel. To the best of our knowledge, the work in this thesis constitutes the first time that (1) an atom switch and a delay line have been demonstrated using blue detuned unnels and (2) the atom-tunnel dynamics and thephase-space distribution of a non-interacting dilute gas in a non-equilibrium state has been tracked experimentally.

•Jan 1, 2011•0 citations

All optical guiding and splitting of a cold atomic beam

D. P. Rhodes, J. Livesey, Gavin P. T. Lancaster +2 more

Summary form only given. The widespread use of magneto-optical traps (MOT) and the development of BEC over the last 10 years have led to the field of atom optics. This field requires the use of equivalent elements to optical mirrors, lenses and beam splitters. The generation of a large deviation atomic beam splitter is one of the most important goals, as it allows the construction of atom interferometers. Optical methods for achieving these elements are enticing, as the use of laser beams would make it easier to alter parameters of your guides within a vacuum chamber. Recent work has demonstrated the use of optical beams to guide and split atoms from a cold atom source. Here we present novel experimental studies of the optical guiding (in both the red- and blue-detuned regime) of a low-velocity intense source (LVIS) of atoms emanating from a rubidium MOT.

Quantum Electronics and Laser Science Conference•Jun 25, 2003•0 citations

Atom guiding along high order Laguerre–Gaussian light beams formed by spatial light modulation

D. P. Rhodes, David M. Gherardi, J. Livesey +4 more

A spatial light modulator (SLM) has been used to create high quality Laguerre–Gaussian (LG) light beams, which have been used to study the guiding of cold rubidium atoms. The SLM allows real-time variation of the hollow guiding beam and permits direct comparison of the guided atom fluxes for different LG modes with minimal adjustment of the other optical components. It is demonstrated that, by increasing the azimuthal index l of the Laguerre–Gaussian beam, the radiation pressure pushing the trapped atoms may be reduced while maintaining the same guided flux. This is the first comparative study of hollow beam atom guiding, and further demonstrates the versatility of the SLM for studies in atom optics.

Journal of Modern Optics•Jan 10, 2006•57 citations

Atom guiding in free-space light beams and photonic crystal fibres

J. Livesey

In this thesis I describe experimental work and present data on the guiding of \nRubidium atoms along free-space propagating light beams as well as within hollow \ncore glass fibres, namely photonic crystal fibres. I describe experiments, laser systems \nand vacuum trap assemblies designed to facilitate this guiding. \nThese experiments are intended to aid progression within the field of cold \natom guidance wherein narrow diameter, long distance hollow-fibre guides are a \ncurrent goal. Realisation of these guides could lead to promising applications such as \natom interferometers and spatially accurate, multi-source, atom depositors. \nHerein, guided fluxes are observed in free-space guiding experiments for \ndistances up to 50mm and up to 10GHz red-detuning from resonance. Additionally \nhollow-core, Kagome structured, quasi- and true-photonic crystal fibres are \ncharacterised. Finally a number of detailed fibre-guiding magneto-optic traps are \ndeveloped. \nBoth cold atomic-beams and cold atomic clouds are reliably positioned above \nfibre entrance facets in conjunction with a guiding laser beam coupled into the fibre \ncore. \nIssues regarding optical flux detection outwith fibre confinement appear to \nhave hindered observation of guided atoms. A far more sensitive detection system has \nbeen developed for use in current, ongoing fibre-guide experiments.

•Jan 1, 2007•0 citations

Cold atom guidance using a binary spatial light modulator

Fredrik K. Fatemi, Mark Bashkansky

We have guided cold (85)Rb atoms in a blue-detuned, high-order hollow laser beam generated by a binary spatial light modulator. The binary holograms written to the modulator produce smooth hollow laser beams with steep intensity walls that can be updated with a 1.6 kHz refresh rate. We analyze the guiding laser beams numerically and experimentally, and show that the atoms are exposed to an average intensity that is ~2% of the maximum intensity of the guide at a laser detuning of 1 GHz and 2 mW of optical power.

Optics Express•Feb 20, 2006•38 citations

Atom guiding along "non-diffracting" light beams

Jochen Arlt, C. A. McQueen, Kishan Dholakia

Summary form only given. Recent advances in cold atom physics have seen the emergence of the area of atom guiding along hollow core optical fibres and also along light beams. Both employ the optical dipole force which for suitably tuned light can restrict the atoms to the dark hollow region of the fibre or the light beam. In this work, we discuss and analyse a novel scheme of channelling cold atoms into a high-order Bessel beam (via a high-order Laguerre-Gaussian beam) and demonstrate an efficient method of producing such beams.

Quantum Electronics and Laser Science Conference•Jan 20, 2003•0 citations
This thesis is concerned with the guiding of cold atoms using optical forces, which is of great importance in the field of atom optics. Atomic beams can be used for precision sensor equipment, building nano-scale structures, construction of quantum computers and to further the understanding of the properties of atoms. Atoms are guided along light beams using the dipole force; there are two regimes under which this force works. Typically red-detuned guides are used (atoms are attracted towards the light) such guides, however, require large detuning and high powers. In this thesis we investigate the use of blue-detuned (atoms are repelled from the light) hollow light beams of moderate power (a few hundred mW) and confine atoms in the dark centre of the beams. Several magneto-optical traps (MOTs) have been constructed to exploit different guiding geometries. Hollow beams have been generated using a variety of methods; in particular the use of a computer controlled spatial light modulator (SLM) has provided great versatility and simplicity to the experimental arrangements. First, experiments were performed with a low-velocity intense source (LVIS) of atoms. A co-linear LG beam significantly enhances the observed flux, however, considerable difficulties are encountered loading atoms into oblique guides. Imaging a hole in the walls of the light tube was used to improve the loading efficiency. Second, guiding a free-falling atom cloud is performed using a non-diffracting Bessel beam. It is found that while the potential of the Bessel beam is steeper than equivalent LG beams the power distribution across the beam severely limits its usefulness. The next study investigated higher-order LG guide beams generated with an SLM. High order modes have a narrower profile so confine the atoms with less interaction with the guide beam, leading to a more natural guide (as opposed to a pushing force). Finally the SLM was used to create non-trivial beam shapes for beam splitters and interferometers.
The main objectives of this thesis were to create and investigate properties and applications of all-optical atomic guides, which are potential building blocks for atom optics experiments. Specifically, we investigated experimentally and theoretically the evolution of the transverse and longitudinal atomic distributions in blue-detuned Bessel tunnels. These tunnels provide confining potentials that are comparable to or higher than the average kinetic energy of cold hundreds of microKelvin) ensembles. The new work highlighted in this thesis include investigations of the following: 1) the generation of Bessel beams using a 2D spatial light modulator (SLM) (both experimental measurement and numerical simulations were performed), 2) the efficiency of the SLM for converting light from a Gaussian beam to a Bessel beam, 3) the behavior of several propagating structures that might be useful for guiding atoms, 4) the atom-tunnel dynamics, 5) an atom switch and delay line (along with measurements of the switch efficiency), and 6) the single-mode propagation in an idealized tunnel. To the best of our knowledge, the work in this thesis constitutes the first time that (1) an atom switch and a delay line have been demonstrated using blue detuned unnels and (2) the atom-tunnel dynamics and thephase-space distribution of a non-interacting dilute gas in a non-equilibrium state has been tracked experimentally.
Summary form only given. The widespread use of magneto-optical traps (MOT) and the development of BEC over the last 10 years have led to the field of atom optics. This field requires the use of equivalent elements to optical mirrors, lenses and beam splitters. The generation of a large deviation atomic beam splitter is one of the most important goals, as it allows the construction of atom interferometers. Optical methods for achieving these elements are enticing, as the use of laser beams would make it easier to alter parameters of your guides within a vacuum chamber. Recent work has demonstrated the use of optical beams to guide and split atoms from a cold atom source. Here we present novel experimental studies of the optical guiding (in both the red- and blue-detuned regime) of a low-velocity intense source (LVIS) of atoms emanating from a rubidium MOT.
A spatial light modulator (SLM) has been used to create high quality Laguerre–Gaussian (LG) light beams, which have been used to study the guiding of cold rubidium atoms. The SLM allows real-time variation of the hollow guiding beam and permits direct comparison of the guided atom fluxes for different LG modes with minimal adjustment of the other optical components. It is demonstrated that, by increasing the azimuthal index l of the Laguerre–Gaussian beam, the radiation pressure pushing the trapped atoms may be reduced while maintaining the same guided flux. This is the first comparative study of hollow beam atom guiding, and further demonstrates the versatility of the SLM for studies in atom optics.
In this thesis I describe experimental work and present data on the guiding of \nRubidium atoms along free-space propagating light beams as well as within hollow \ncore glass fibres, namely photonic crystal fibres. I describe experiments, laser systems \nand vacuum trap assemblies designed to facilitate this guiding. \nThese experiments are intended to aid progression within the field of cold \natom guidance wherein narrow diameter, long distance hollow-fibre guides are a \ncurrent goal. Realisation of these guides could lead to promising applications such as \natom interferometers and spatially accurate, multi-source, atom depositors. \nHerein, guided fluxes are observed in free-space guiding experiments for \ndistances up to 50mm and up to 10GHz red-detuning from resonance. Additionally \nhollow-core, Kagome structured, quasi- and true-photonic crystal fibres are \ncharacterised. Finally a number of detailed fibre-guiding magneto-optic traps are \ndeveloped. \nBoth cold atomic-beams and cold atomic clouds are reliably positioned above \nfibre entrance facets in conjunction with a guiding laser beam coupled into the fibre \ncore. \nIssues regarding optical flux detection outwith fibre confinement appear to \nhave hindered observation of guided atoms. A far more sensitive detection system has \nbeen developed for use in current, ongoing fibre-guide experiments.
We have guided cold (85)Rb atoms in a blue-detuned, high-order hollow laser beam generated by a binary spatial light modulator. The binary holograms written to the modulator produce smooth hollow laser beams with steep intensity walls that can be updated with a 1.6 kHz refresh rate. We analyze the guiding laser beams numerically and experimentally, and show that the atoms are exposed to an average intensity that is ~2% of the maximum intensity of the guide at a laser detuning of 1 GHz and 2 mW of optical power.
Summary form only given. Recent advances in cold atom physics have seen the emergence of the area of atom guiding along hollow core optical fibres and also along light beams. Both employ the optical dipole force which for suitably tuned light can restrict the atoms to the dark hollow region of the fibre or the light beam. In this work, we discuss and analyse a novel scheme of channelling cold atoms into a high-order Bessel beam (via a high-order Laguerre-Gaussian beam) and demonstrate an efficient method of producing such beams.