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

Chinese Physics Letters

Atomic Funnel Composed of an HE 11 -Mode Output Hollow Beam

Ni Yun, Liu Nan-Chun, Yin Jian-Ping

Published Jun 17, 2003• 1 citation
Publisher

Abstract

Using exact solutions of Maxwell equations based on the vector model, we calculate the diffracted near- and far-field distributions of the HE 11 -mode output beam from a micron-sized hollow optical fibre under the Fresnel approximation, and compare the differences between the HE 11 - and LP 01 -mode output beams. Our study shows that it is unsuitable to calculate the diffracted near-field distribution of the hollow fibre by using weakly waveguiding approximation, and the near- and far-field intensity distributions of the HE 11 -mode output beam are doughnut-like, which can be used to form a simple atomic funnel as it is blue-detuned.

DOI
10.1088/0256-307x/20/7/324

Related papers

Diffracted field distributions from the HE11mode in a hollow optical fibre for an atomic funnel

Yun Ni, Nanchun Liu, Jianping Yin

The diffracted near field distribution from an LP 01 mode in a hollow optical fibre was recently calculated using a scalar model based on the weakly waveguiding approximation (Yoo et al 1999 J. Opt. B: Quantum Semiclass. Opt. 1 364 ). It showed a dominant Gaussian-like distribution with an increased axial intensity in the central region (not a doughnut-like distribution), so the diffracted output beam from the hollow fibre cannot be used to form an atomic funnel. Using exact solutions of the Maxwell equations based on a vector model, however, we calculate the electric field and intensity distributions of the HE 11 mode in the same hollow fibre and study the diffracted near- and far-field distributions of the HE 11 -mode output beam under the Fresnel approximation. We analyse and compare the differences between the output beams from the HE 11 and LP 01 modes. Our study shows that both the near- and far-field intensity distributions of the HE 11 -mode output beam are doughnut-like and can be used to form a simple atomic funnel. However, it is not suitable to use the weakly waveguiding approximation to calculate the diffracted near-field distribution of the hollow fibre due to the greater refractive-index difference between the hollow region ( n 0 = 1) and the core ( n 1 = 1.45 or 1.5). Finally, the 3D intensity distribution of the HE 11 -mode output beam is modelled and the corresponding optical potentials for cold atoms are calculated. Some potential applications of the HE 11 -mode output beam in an atomic guide and funnel are briefly discussed.

Journal of Optics B Quantum and Semiclassical Optics•May 30, 2003•4 citations

LP 01 -mode output beam from a micro-sized hollow optical fiber: A simple theoretical model and its applications in atom optics

Jianping Yin, Yifu Zhu

We calculate electric field distributions of the output beam from a LP01 mode in a micro-sized hollow optical fiber under the Fresnel approximation and find that the output beam characteristics in free space is similar to that of a TEM01* doughnut laser beam. We propose a simple theoretical model, a modified TEM01* doughnut beam, to simulate the free-space output beam from the LP01 mode in hollow fibers, and discuss potential applications of the LP01-mode output beam in atomic guiding, funneling, cooling, and trapping. Our study shows that this model is in good agreement with the numerical results derived from the Fresnel diffraction theory (except near the weak first-order diffraction ring around the zero-order diffraction peak). The model can be conveniently used to calculate the optical potential, gradient force, light-induced acceleration, spontaneous-emission rate, and quantum tunneling loss in atomic guiding, funneling, and trapping with the LP01-mode output beam in free space. It can be also used to study the optical-potential evaporative cooling of cold atoms in a gravito-optical trap constructed by the LP01-mode output beam.

Journal of Applied Physics•Mar 1, 1999•18 citations

Single light mode hollow optical fibres for guiding metastable helium atoms

R. G. Dall, Maarten D. Hoogerland, K. G. H. Baldwin +1 more

Summary form only given. In previous experiments we have guided excited state helium atoms through hollow optical fibres. We employ helium atoms in the metastable 2/sup 3/S/sub 1/ state, and utilise the 1083 nm transition to the 2/sup 3/P/sub 2/ state to manipulate the atomic trajectories. For these atom guiding experiments, metastable helium has the inherent advantages of near unity detection efficiency and low background counts, since metastable helium de-excites on collision with the fibre wall. We have manufactured hollow fibres with a range of dimensions, some of which support single optical mode propagation. The fibres consist of a narrow (few /spl mu/m) light guiding region around the hole, surrounded by a 20-30 /spl mu/m thick region of lower refractive index. Propagation of the lowest order mode has been observed, thereby indicating that a uniform evanescent field can be created on the inside fibre wall. In addition, excitation of the two orthogonal modes has been observed under slightly different input coupling conditions. The resulting output from the fibre yields a hollow optical beam which has the potential to funnel atoms into the fibre. The results of atom guiding experiments using these fibres are presented.

Conference on Lasers and Electro-Optics•Aug 29, 2005•0 citations

Evanescent light-wave atomic funnel: A tandem hollow-fiber, hollow-beam approach

Jianping Yin, Yifu Zhu, Yuzhu Wang

We propose an atomic funnel consisting of a dark hollow, divergent laser beam and an evanescent light in a short micron-sized hollow optical fiber. The cold atoms extracted from a magneto-optical trap experience effective Sisyphus cooling in the dark hollow beam. We calculate the potential barriers for atomic guiding in the evanescent light and the dark hollow beam, and analyze the atomic losses during the guiding and funneling process. Our results show that the equilibrium three-dimensional root-mean-square momentum of about $4.5\ensuremath{\Elzxh}k$ (temperature $\ensuremath{\sim}2.5\ensuremath{\mu}\mathrm{K}$) and the funneling efficiency of about 95% could be obtained. A low-velocity, intense coherent atomic beam can be generated in this funnel scheme and its potential applications in atom optics are briefly discussed.

Physical Review A•Mar 1, 1998•42 citations

Tunable doughnut light beam for a near-field optical funnel of atoms

S. M. Iftiquar, Hajime Ito, Motoichi Ohtsu

A doughnut-shaped Laguerre-Gaussian (LG) beam has been generated through interference of two spherical waves. The beam has a 5 mm bright ring and a 250-microns dark center suitable for our atom funnel experiment. The power conversion efficiency from a Gaussian mode to the LG mode is about 50%.

Conference on Lasers and Electro-Optics Pacific Rim (CLEO-PR)•Nov 13, 2002•2 citations

An optically-guided atomic fountain

Kihwan Kim, Xinye Xu, Heung‐Ryoul Noh +1 more

Summary form only given. The optical guidance of cold atoms by the hollow laser beam (HLB) with blue detuning has been well understood experimentally and theoretically (Xinye Xu et al, 2000). Based on this clear understanding and the development of an efficient atomic guiding, we have performed the experiment of optically guided atomic fountain by using a blue-detuned cylindrical HLB. An HLB was generated from a micron-sized hollow optical fiber and collimated by the objective lens and propagates downwards to the center of a magneto-optical trap (MOT). We have demonstrated tenfold enhancement of the atom-funneling efficiency for the HLB-guided atomic fountain, which may lead to improved performance of atom optical experiments based on the atomic fountain such as the Rb atomic clock.

Quantum Electronics and Laser Science Conference•Nov 13, 2002•1 citation
Using exact solutions of Maxwell equations based on the vector model, we calculate the diffracted near- and far-field distributions of the HE 11 -mode output beam from a micron-sized hollow optical fibre under the Fresnel approximation, and compare the differences between the HE 11 - and LP 01 -mode output beams. Our study shows that it is unsuitable to calculate the diffracted near-field distribution of the hollow fibre by using weakly waveguiding approximation, and the near- and far-field intensity distributions of the HE 11 -mode output beam are doughnut-like, which can be used to form a simple atomic funnel as it is blue-detuned.
The diffracted near field distribution from an LP 01 mode in a hollow optical fibre was recently calculated using a scalar model based on the weakly waveguiding approximation (Yoo et al 1999 J. Opt. B: Quantum Semiclass. Opt. 1 364 ). It showed a dominant Gaussian-like distribution with an increased axial intensity in the central region (not a doughnut-like distribution), so the diffracted output beam from the hollow fibre cannot be used to form an atomic funnel. Using exact solutions of the Maxwell equations based on a vector model, however, we calculate the electric field and intensity distributions of the HE 11 mode in the same hollow fibre and study the diffracted near- and far-field distributions of the HE 11 -mode output beam under the Fresnel approximation. We analyse and compare the differences between the output beams from the HE 11 and LP 01 modes. Our study shows that both the near- and far-field intensity distributions of the HE 11 -mode output beam are doughnut-like and can be used to form a simple atomic funnel. However, it is not suitable to use the weakly waveguiding approximation to calculate the diffracted near-field distribution of the hollow fibre due to the greater refractive-index difference between the hollow region ( n 0 = 1) and the core ( n 1 = 1.45 or 1.5). Finally, the 3D intensity distribution of the HE 11 -mode output beam is modelled and the corresponding optical potentials for cold atoms are calculated. Some potential applications of the HE 11 -mode output beam in an atomic guide and funnel are briefly discussed.
We calculate electric field distributions of the output beam from a LP01 mode in a micro-sized hollow optical fiber under the Fresnel approximation and find that the output beam characteristics in free space is similar to that of a TEM01* doughnut laser beam. We propose a simple theoretical model, a modified TEM01* doughnut beam, to simulate the free-space output beam from the LP01 mode in hollow fibers, and discuss potential applications of the LP01-mode output beam in atomic guiding, funneling, cooling, and trapping. Our study shows that this model is in good agreement with the numerical results derived from the Fresnel diffraction theory (except near the weak first-order diffraction ring around the zero-order diffraction peak). The model can be conveniently used to calculate the optical potential, gradient force, light-induced acceleration, spontaneous-emission rate, and quantum tunneling loss in atomic guiding, funneling, and trapping with the LP01-mode output beam in free space. It can be also used to study the optical-potential evaporative cooling of cold atoms in a gravito-optical trap constructed by the LP01-mode output beam.
Summary form only given. In previous experiments we have guided excited state helium atoms through hollow optical fibres. We employ helium atoms in the metastable 2/sup 3/S/sub 1/ state, and utilise the 1083 nm transition to the 2/sup 3/P/sub 2/ state to manipulate the atomic trajectories. For these atom guiding experiments, metastable helium has the inherent advantages of near unity detection efficiency and low background counts, since metastable helium de-excites on collision with the fibre wall. We have manufactured hollow fibres with a range of dimensions, some of which support single optical mode propagation. The fibres consist of a narrow (few /spl mu/m) light guiding region around the hole, surrounded by a 20-30 /spl mu/m thick region of lower refractive index. Propagation of the lowest order mode has been observed, thereby indicating that a uniform evanescent field can be created on the inside fibre wall. In addition, excitation of the two orthogonal modes has been observed under slightly different input coupling conditions. The resulting output from the fibre yields a hollow optical beam which has the potential to funnel atoms into the fibre. The results of atom guiding experiments using these fibres are presented.
We propose an atomic funnel consisting of a dark hollow, divergent laser beam and an evanescent light in a short micron-sized hollow optical fiber. The cold atoms extracted from a magneto-optical trap experience effective Sisyphus cooling in the dark hollow beam. We calculate the potential barriers for atomic guiding in the evanescent light and the dark hollow beam, and analyze the atomic losses during the guiding and funneling process. Our results show that the equilibrium three-dimensional root-mean-square momentum of about $4.5\ensuremath{\Elzxh}k$ (temperature $\ensuremath{\sim}2.5\ensuremath{\mu}\mathrm{K}$) and the funneling efficiency of about 95% could be obtained. A low-velocity, intense coherent atomic beam can be generated in this funnel scheme and its potential applications in atom optics are briefly discussed.
Summary form only given. The optical guidance of cold atoms by the hollow laser beam (HLB) with blue detuning has been well understood experimentally and theoretically (Xinye Xu et al, 2000). Based on this clear understanding and the development of an efficient atomic guiding, we have performed the experiment of optically guided atomic fountain by using a blue-detuned cylindrical HLB. An HLB was generated from a micron-sized hollow optical fiber and collimated by the objective lens and propagates downwards to the center of a magneto-optical trap (MOT). We have demonstrated tenfold enhancement of the atom-funneling efficiency for the HLB-guided atomic fountain, which may lead to improved performance of atom optical experiments based on the atomic fountain such as the Rb atomic clock.