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

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE

Generation of a dark hollow beam by a four-step phase plate and its application for manipulating cold atoms

Ji Xian-Ming, Renwang Mu, Jinghuai Fang, Shuwu Xu, Liangkai Han

Published Jan 11, 2005• 2 citations
Publisher

Abstract

In this paper, we propose a new scheme to generate a dark hollow-beam, which includes dark hollow-beam optical pipe and hollow-beam optical dipole trap, through using a system composed of a four steps phase plate and a spherical lens. This kind of light beam can be used to focus, guide and trap the cold atom. We also calculate the intensity distributing and characteristic parameters of a dark hollow-beam and the optical dipole potential which manipulate the cold atoms of 85Rb. At last, we analyze and demonstrate the experimental feasibility of the scheme.

DOI
10.1117/12.577724

Related papers

Generation of a focused hollow beam by an 2pi-phase plate and its application in atom or molecule optics

Yong Xia, Jianping Yin

We propose a new scheme to generate a focusing hollow beam (FHB) by use of an azimuthally distributed 2pi-phase plate and a convergent thin lens. From the Fresnel diffraction theory, we calculate the intensity distributions of the FHB in free propagation space and study the relationship between the waist w_0 of the incident Gaussian beam (or the focal length f of the lens) and the dark spot size (or the beam radius) at the focal point and the relationship between the maximum radial intensity of the FHB and the dark spot size (or the beam radius) at the focal point, respectively. Our study shows that the FHB can be used to cool and trap neutral atoms by intensity-gradient-induced Sisyphus cooling due to an extremely high intensity gradient of the FHB itself near the focal point, or to guide and focus a cold molecular beam. We also calculate the optical potential of the blue-detuned FHB for ^85Rb atoms and find that in the focal plane, the smaller the dark spot size of the FHB is, the higher the optical potential is, and the greater the corresponding optimal detuning delta is; these qualities are beneficial to an atomic lens not only because it is profitable to obtain an atomic lens with a higher resolution, but also because it is helpful to reduce the spontaneous photon-scattering effect of atoms in the FHB.

Journal of the Optical Society of America B•Mar 1, 2005•30 citations

A novel array of surface hollow optical micro-traps

Ji Xian-Ming, Renwang Mu, Yin Jianping +1 more

In this paper, we propose a new scheme to form an array of surface hollow optical micro-traps for cold atoms (or molecules) by using a phase grating with four phase steps and an array of microlens, study the intensity distribution of 2D array of surface hollow optical micro-traps, and calculate the corresponding optical potential for cold 85Rb atoms, and discuss some potential applications of our hollow micro-trap array in atom and molecule optics. Our study shows that when our grating-lens system is illuminated by YAG laser with a power of 1W, a 2D array of surface hollow optical traps with 104 micro-wells will be generated in an area of 1cm2. Each optical trap has some novel characteristics, such as smaller trapping volume, higher effective intensity and its intensity gradient. The corresponding optical potential for trapped 85Rb atoms can reach 190μK, which is high enough to trap cold atoms or cold molecules, and can be used to realize an all-optical atomic and molecular Bose-Einstein condensations, even to prepare novel optical lattices, and so on.

Acta Physica Sinica•Jan 1, 2005•3 citations

Generation of One-Dimensional Array of Focused Hollow-Beam Pipes and Its Surface Microscopic Waveguide for Cold Atoms or Molecules

Ji Xian-Ming, Yong Xia, Yin Jian-Ping

We propose a new scheme to guide cold atoms (or molecules) by using a one-dimensional (1D) array of focused hollow-beam pipes generated by the combination of a binary phase grating and a 1D array of micro-cylindrical lenses on the substrate surface. We also calculate the intensity distribution of the focused hollow-beam pipe array and its optical potential for 85 Rb atoms. The result shows that when the blue detuning of the incident beam and its intensity are 10 GHz and 7.0×10 3 W/m 2 respectively, the horizontal dark spot size of each focused hollow-beam pipe and the efficient optical potential are 4.4 μm and ~0.23 mK, which is high enough to guide cold 85 Rb atoms (~20 μK) from a standard optical molasses and then to realize the 1D array of surface atomic waveguides on an atom chip.

Chinese Physics Letters•Jul 1, 2004•2 citations

An Atomic Lens Using a Focusing Hollow Beam

Yong Xia, Yin Jian-Ping, Yuzhu Wang

We propose a new method to generate a focused hollow laser beam by using an azimuthally distributed 2π-phase plate and a convergent thin lens, and calculate the intensity distribution of the focused hollow beam in free propagation space. The relationship between the waist w o of the incident collimated Gaussian beam and the dark spot size of the focused hollow beam at the focal point, and the relationship between the focal length f of the thin lens and the dark spot size are studied respectively. The optical potential of the blue-detuned focused hollow beam for 85 Rb atoms is calculated. Our study shows that when the larger waist w of the incident Gaussian beam and the shorter focal length f of the lens are chosen, we can obtain an extremely small dark spot size of the focused hollow beam, which can be used to form an atomic lens with a resolution of several angstroms.

Chinese Physics Letters•Apr 24, 2003•7 citations

Generation of one- or two-dimensional arrays of hollow optical microtraps for cold atoms, molecules, or microparticles on a chip

Renwang Mu, LU Jun-fa, Shuwu Xu +2 more

We propose a new scheme to form 1D or 2D arrays of hollow optical microtraps for cold atoms, molecules, or microscopy particles on a chip by using an optical system composed of a four-step phase grating and a 2D array of microlenses. We calculate the intensity distribution of the 2D array of the hollow optical microtraps and its optical potential for 85Rb atoms and discuss its potential applications in atom and molecule optics. Our study shows that when our optical system is illuminated by a 1 W Ti:Sapphire laser, 103 hollow optical microtraps can be generated. Each optical microtrap has a small trapping volume and a high effective intensity, and its intensity gradient and the optical dipole potential for 85Rb atoms can reach 167 μK. Characteristic parameters of each optical microtrap can be changed by adjusting the parameters of our optical system, which can be used to satisfy real needs of various experiments to manipulate and control cold atoms, molecules, or microscopy particles.

Journal of the Optical Society of America B•Dec 12, 2008•5 citations

Theoretical and experimental study of a controllable double-dark-hollow beam

Qi Zhou, Lu Jun-Fa, Yin Jian-Ping

A novel scheme is proposed for a double-dark-hollow beam (DDHB) based on non-full-range phase modulation with double-period. Upon illumination by a collimated He-Ni laser beam shaped by a round hole with a radius of 1.5 mm, the DDHB with an axial length of 30 mm, a width of 0.110.14 mm for each dark hollow beam and their separated distance being 57.6 m is generated in the image space of lens with a focal length of 200 mm. The proposed scheme has the advantages of simple construction and high controllability, and the separated distance between the two light pipes is only dependent on the factor of phase modulation of p. Under the given conditions, a reversible evolution process from a DDHB to a single dark hollow beam (SDHB) can be realized. Experiments for our scheme are performed, results of which are consistent with the theoretical ones. A valuable expansion of the application of DDHB in blue-detuned optical trapping is also discussed. Double and four well hollow optical traps, even the hollow optical lattices can be obtained by using various spatial combinations of our DDHB. The proposed DDHB is expected to play an important role in the study of trapping and manipulation of cold atoms or molecules.

Acta Physica Sinica•Jan 1, 2015•2 citations
In this paper, we propose a new scheme to generate a dark hollow-beam, which includes dark hollow-beam optical pipe and hollow-beam optical dipole trap, through using a system composed of a four steps phase plate and a spherical lens. This kind of light beam can be used to focus, guide and trap the cold atom. We also calculate the intensity distributing and characteristic parameters of a dark hollow-beam and the optical dipole potential which manipulate the cold atoms of 85Rb. At last, we analyze and demonstrate the experimental feasibility of the scheme.
We propose a new scheme to generate a focusing hollow beam (FHB) by use of an azimuthally distributed 2pi-phase plate and a convergent thin lens. From the Fresnel diffraction theory, we calculate the intensity distributions of the FHB in free propagation space and study the relationship between the waist w_0 of the incident Gaussian beam (or the focal length f of the lens) and the dark spot size (or the beam radius) at the focal point and the relationship between the maximum radial intensity of the FHB and the dark spot size (or the beam radius) at the focal point, respectively. Our study shows that the FHB can be used to cool and trap neutral atoms by intensity-gradient-induced Sisyphus cooling due to an extremely high intensity gradient of the FHB itself near the focal point, or to guide and focus a cold molecular beam. We also calculate the optical potential of the blue-detuned FHB for ^85Rb atoms and find that in the focal plane, the smaller the dark spot size of the FHB is, the higher the optical potential is, and the greater the corresponding optimal detuning delta is; these qualities are beneficial to an atomic lens not only because it is profitable to obtain an atomic lens with a higher resolution, but also because it is helpful to reduce the spontaneous photon-scattering effect of atoms in the FHB.
In this paper, we propose a new scheme to form an array of surface hollow optical micro-traps for cold atoms (or molecules) by using a phase grating with four phase steps and an array of microlens, study the intensity distribution of 2D array of surface hollow optical micro-traps, and calculate the corresponding optical potential for cold 85Rb atoms, and discuss some potential applications of our hollow micro-trap array in atom and molecule optics. Our study shows that when our grating-lens system is illuminated by YAG laser with a power of 1W, a 2D array of surface hollow optical traps with 104 micro-wells will be generated in an area of 1cm2. Each optical trap has some novel characteristics, such as smaller trapping volume, higher effective intensity and its intensity gradient. The corresponding optical potential for trapped 85Rb atoms can reach 190μK, which is high enough to trap cold atoms or cold molecules, and can be used to realize an all-optical atomic and molecular Bose-Einstein condensations, even to prepare novel optical lattices, and so on.
We propose a new scheme to guide cold atoms (or molecules) by using a one-dimensional (1D) array of focused hollow-beam pipes generated by the combination of a binary phase grating and a 1D array of micro-cylindrical lenses on the substrate surface. We also calculate the intensity distribution of the focused hollow-beam pipe array and its optical potential for 85 Rb atoms. The result shows that when the blue detuning of the incident beam and its intensity are 10 GHz and 7.0×10 3 W/m 2 respectively, the horizontal dark spot size of each focused hollow-beam pipe and the efficient optical potential are 4.4 μm and ~0.23 mK, which is high enough to guide cold 85 Rb atoms (~20 μK) from a standard optical molasses and then to realize the 1D array of surface atomic waveguides on an atom chip.
We propose a new method to generate a focused hollow laser beam by using an azimuthally distributed 2π-phase plate and a convergent thin lens, and calculate the intensity distribution of the focused hollow beam in free propagation space. The relationship between the waist w o of the incident collimated Gaussian beam and the dark spot size of the focused hollow beam at the focal point, and the relationship between the focal length f of the thin lens and the dark spot size are studied respectively. The optical potential of the blue-detuned focused hollow beam for 85 Rb atoms is calculated. Our study shows that when the larger waist w of the incident Gaussian beam and the shorter focal length f of the lens are chosen, we can obtain an extremely small dark spot size of the focused hollow beam, which can be used to form an atomic lens with a resolution of several angstroms.
We propose a new scheme to form 1D or 2D arrays of hollow optical microtraps for cold atoms, molecules, or microscopy particles on a chip by using an optical system composed of a four-step phase grating and a 2D array of microlenses. We calculate the intensity distribution of the 2D array of the hollow optical microtraps and its optical potential for 85Rb atoms and discuss its potential applications in atom and molecule optics. Our study shows that when our optical system is illuminated by a 1 W Ti:Sapphire laser, 103 hollow optical microtraps can be generated. Each optical microtrap has a small trapping volume and a high effective intensity, and its intensity gradient and the optical dipole potential for 85Rb atoms can reach 167 μK. Characteristic parameters of each optical microtrap can be changed by adjusting the parameters of our optical system, which can be used to satisfy real needs of various experiments to manipulate and control cold atoms, molecules, or microscopy particles.
A novel scheme is proposed for a double-dark-hollow beam (DDHB) based on non-full-range phase modulation with double-period. Upon illumination by a collimated He-Ni laser beam shaped by a round hole with a radius of 1.5 mm, the DDHB with an axial length of 30 mm, a width of 0.110.14 mm for each dark hollow beam and their separated distance being 57.6 m is generated in the image space of lens with a focal length of 200 mm. The proposed scheme has the advantages of simple construction and high controllability, and the separated distance between the two light pipes is only dependent on the factor of phase modulation of p. Under the given conditions, a reversible evolution process from a DDHB to a single dark hollow beam (SDHB) can be realized. Experiments for our scheme are performed, results of which are consistent with the theoretical ones. A valuable expansion of the application of DDHB in blue-detuned optical trapping is also discussed. Double and four well hollow optical traps, even the hollow optical lattices can be obtained by using various spatial combinations of our DDHB. The proposed DDHB is expected to play an important role in the study of trapping and manipulation of cold atoms or molecules.