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

Physical Review A

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

Jianping Yin, Yifu Zhu, Yuzhu Wang

Published Mar 1, 1998• 42 citations
Publisher

Abstract

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.

DOI
10.1103/physreva.57.1957

Related papers

Atomic funnel with evanescent light

Hajime Ito, K. Sakaki, Wonho Jhe +1 more

We propose an atomic funnel composed of an evanescent-light mirror produced in a conical hollow prism. The funneling of cold Rb atoms released from a magneto-optical trap is simulated in the scheme of the evanescent-light-induced Sisyphus cooling for compensating the heating by gravity. A geometric method of the conversion of a Gaussian light beam into a doughnut-shaped light beam suitable for the atomic funnel is also experimentally demonstrated by means of a double-cone prism. Under the assumption of a proper optical intensity distribution over the inner surface of a specific conical hollow prism, the Monte Carlo simulation including the van der Waals interaction shows that a half of the released Rb atoms can be collected and the mean temperature of the collected atoms is low enough for the application to be guided with a bent hollow optical fiber.

Physical Review A•Jul 1, 1997•77 citations

Atom guiding and cooling in a dark hollow laser beam

Jianping Yin, Yifu Zhu, Wonho Jhe +1 more

We propose and analyze theoretically a scheme for atomic guiding and cooling in a dark hollow laser beam generated from the collimated output beam of a ${\mathrm{LP}}_{01}$ mode in a micrometer-sized hollow optical fiber. In the scheme, cold atoms from a magneto-optical trap are loaded into the blue-detuned dark hollow beam, move down in the dark hollow beam, and experience transverse Sisyphus cooling induced by the dark hollow beam and a weak repumping beam. In the longitudinal direction, the guided atoms experience heating from the gravity field and cooling from the upward-propagating dark hollow beam and repumping beam. We estimate the transverse two-dimensional equilibrium temperature, the final longitudinal mean velocity, and the total loss of the guided atoms. Our calculations show that a transverse equilibrium temperature of $\ensuremath{\sim}1.2\ensuremath{\mu}\mathrm{K},$ a final longitudinal mean velocity of 0--4.41 m/s, and a guiding efficiency of 65--95 % may be obtained.

Physical Review A•Jul 1, 1998•107 citations

Laser cooling and trapping of atoms in optical and micro-wave electro-magnetic trap

Y.Z. Wang, Jihui Ying, Qinghong Zhou +2 more

Presents work on the realization of Bose-Einstein condensates (BEC) in optical and electro-magnetic traps. We have done some theoretical and experimental work on the project. We have proposed an optical funnel or a hollow beam, which are produced from a short micron-sized hollow optical fiber or a set-up of lenses. The cold atoms extracted from an magneto-optical trap experience effective Sisyphus cooling in the dark hollow beam. We calculate the potential barriers for atomic guiding in the dark hollow beam, and analyze the atomic losses during the guiding process. Inside the hollow beam atoms experience an efficient Sisyphus cooling and repumping-beam induced geometric cooling. We have estimated the total loss rate of the cold atoms, and it shows that an ultracold and dense Rb atomic sample with a 3D temperature of /spl sim/1 K can be obtained and the appearance of an optically-trapped Bose-Einstein condensation may be possible in this optical trap. We have also made a proposal of a micro-wave electro-magnetic trap, which is working at the frequency which is very far from the optical transition of the cold atoms. The trapping force comes from the interaction between the electro-magnetic induced magnetic dipole moment with the electro-magnetic field. Theoretical calculation shows that the force can be used to trap the cold atoms in the trap.

Conference on Lasers and Electro-Optics Pacific Rim (CLEO-PR)•Jan 20, 2003•0 citations

Optical potential for atom guidance in a dark hollow laser beam

Jianping Yin, Yifu Zhu, Wenbao Wang +2 more

We analyze the optical potential for atom guidance in a dark hollow laser beam and compare it with that generated by the evanescent wave in a micrometer-sized hollow optical fiber. We calculate dependence of the optical potential on various parameters: radial position r, laser–atom detuning Δ, beam power P0, and propagation distance Z. We experimentally generated a dark hollow laser beam from a hollow optical fiber with a 7-μm hole diameter and obtained a coupling efficiency of ∼50% for the LP01 mode. Our study shows that a dark hollow laser beam can produce an optical potential deep enough to guide cold atoms from a magneto-optical trap.

Journal of the Optical Society of America B•Jan 1, 1998•86 citations

Atomic funnel with evanescent waves

Hajime Ito, Keiji Sakaki, Toshiyuki Nakata +2 more

Summary form only given. Cold atoms are expected to be applied to experiments on quantum motion, topological phenomena, cavity QED, and so on. Most of the interesting experiments require precise control on atomic motion. We have proposed the atomic waveguide by evanescent waves to enable the precise one-dimensional manipulation of atoms. The atomic waveguide is composed of a cylindrical-core hollow fiber with a hollow diameter of a few microns. The attachment of a funnel for atoms should be effective in coupling atoms to the atomic waveguide. In this work we present a novel scheme of the atomic funnel based on the dipole force from evanescent waves. Compared to the 2D MOT funnel, the evanescent-wave funnel has a further advantage of acting as a gravitational trap.

Quantum Electronics and Laser Science Conference•Jun 7, 1996•1 citation

Atom guiding and cooling by a dark hollow laser beam

Kwanil Lee, Xinye Xu, Seunghyup Yoo +2 more

Atom guiding in an atomic funnel is very useful for many interesting atom optical experiments requiring the precise control of atomic motion. We have obtained a doughnut-shaped laser beam by coupling a Ti:sapphire laser into a hollow core optical fiber and collimating the output laser beam of the fiber with a microscope objective lens. Using such a doughnut-shaped laser beam [2 mm inner diameter and a 5 mm outer diameter at the trapping position (about 1m away from the objective lens)l, we have guided the trapped cold Rb atoms in the atomic funnel.

Conference on Lasers and Electro-Optics Pacific Rim (CLEO-PR)•Jan 20, 2003•1 citation
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\Elzxhk4.5\ensuremath{\Elzxh}k4.5\ensuremath\Elzxhk (temperature \ensuremath∼2.5\ensuremathμK\ensuremath{\sim}2.5\ensuremath{\mu}\mathrm{K}\ensuremath∼2.5\ensuremathμK) 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.
We propose an atomic funnel composed of an evanescent-light mirror produced in a conical hollow prism. The funneling of cold Rb atoms released from a magneto-optical trap is simulated in the scheme of the evanescent-light-induced Sisyphus cooling for compensating the heating by gravity. A geometric method of the conversion of a Gaussian light beam into a doughnut-shaped light beam suitable for the atomic funnel is also experimentally demonstrated by means of a double-cone prism. Under the assumption of a proper optical intensity distribution over the inner surface of a specific conical hollow prism, the Monte Carlo simulation including the van der Waals interaction shows that a half of the released Rb atoms can be collected and the mean temperature of the collected atoms is low enough for the application to be guided with a bent hollow optical fiber.
We propose and analyze theoretically a scheme for atomic guiding and cooling in a dark hollow laser beam generated from the collimated output beam of a LP01{\mathrm{LP}}_{01}LP01​ mode in a micrometer-sized hollow optical fiber. In the scheme, cold atoms from a magneto-optical trap are loaded into the blue-detuned dark hollow beam, move down in the dark hollow beam, and experience transverse Sisyphus cooling induced by the dark hollow beam and a weak repumping beam. In the longitudinal direction, the guided atoms experience heating from the gravity field and cooling from the upward-propagating dark hollow beam and repumping beam. We estimate the transverse two-dimensional equilibrium temperature, the final longitudinal mean velocity, and the total loss of the guided atoms. Our calculations show that a transverse equilibrium temperature of $\ensuremath{\sim}1.2\ensuremath{\mu}\mathrm{K},$ a final longitudinal mean velocity of 0--4.41 m/s, and a guiding efficiency of 65--95 % may be obtained.
Presents work on the realization of Bose-Einstein condensates (BEC) in optical and electro-magnetic traps. We have done some theoretical and experimental work on the project. We have proposed an optical funnel or a hollow beam, which are produced from a short micron-sized hollow optical fiber or a set-up of lenses. The cold atoms extracted from an magneto-optical trap experience effective Sisyphus cooling in the dark hollow beam. We calculate the potential barriers for atomic guiding in the dark hollow beam, and analyze the atomic losses during the guiding process. Inside the hollow beam atoms experience an efficient Sisyphus cooling and repumping-beam induced geometric cooling. We have estimated the total loss rate of the cold atoms, and it shows that an ultracold and dense Rb atomic sample with a 3D temperature of /spl sim/1 K can be obtained and the appearance of an optically-trapped Bose-Einstein condensation may be possible in this optical trap. We have also made a proposal of a micro-wave electro-magnetic trap, which is working at the frequency which is very far from the optical transition of the cold atoms. The trapping force comes from the interaction between the electro-magnetic induced magnetic dipole moment with the electro-magnetic field. Theoretical calculation shows that the force can be used to trap the cold atoms in the trap.
We analyze the optical potential for atom guidance in a dark hollow laser beam and compare it with that generated by the evanescent wave in a micrometer-sized hollow optical fiber. We calculate dependence of the optical potential on various parameters: radial position r, laser–atom detuning Δ, beam power P0, and propagation distance Z. We experimentally generated a dark hollow laser beam from a hollow optical fiber with a 7-μm hole diameter and obtained a coupling efficiency of ∼50% for the LP01 mode. Our study shows that a dark hollow laser beam can produce an optical potential deep enough to guide cold atoms from a magneto-optical trap.
Summary form only given. Cold atoms are expected to be applied to experiments on quantum motion, topological phenomena, cavity QED, and so on. Most of the interesting experiments require precise control on atomic motion. We have proposed the atomic waveguide by evanescent waves to enable the precise one-dimensional manipulation of atoms. The atomic waveguide is composed of a cylindrical-core hollow fiber with a hollow diameter of a few microns. The attachment of a funnel for atoms should be effective in coupling atoms to the atomic waveguide. In this work we present a novel scheme of the atomic funnel based on the dipole force from evanescent waves. Compared to the 2D MOT funnel, the evanescent-wave funnel has a further advantage of acting as a gravitational trap.
Atom guiding in an atomic funnel is very useful for many interesting atom optical experiments requiring the precise control of atomic motion. We have obtained a doughnut-shaped laser beam by coupling a Ti:sapphire laser into a hollow core optical fiber and collimating the output laser beam of the fiber with a microscope objective lens. Using such a doughnut-shaped laser beam [2 mm inner diameter and a 5 mm outer diameter at the trapping position (about 1m away from the objective lens)l, we have guided the trapped cold Rb atoms in the atomic funnel.