Atom trap and waveguide using a two-color evanescent light field around a subwavelength-diameter optical fiber

We suggest using a two-color evanescent light field around a subwavelength-diameter fiber to trap and guide atoms. The optical fiber carries a red-detuned light and a blue-detuned light, with both modes far from resonance. When both input light fields are circularly polarized, a set of trapping minima of the total potential in the transverse plane is formed as a ring around the fiber. This design allows confinement of atoms to a cylindrical shell around the fiber. When one or both of the input light fields are linearly polarized, the total potential has two local minimum points in the transverse plane. This design allows confinement of atoms to two straight lines parallel to the fiber axis. Due to the small thickness of the fiber, we can use far-off-resonance fields with substantially differing evanescent decay lengths to produce a net potential with a large depth, a large coherence time, and a large trap lifetime. For example, a 0.2-\ensuremath{\mu}m-radius silica fiber carrying 30 mW of 1.06-\ensuremath{\mu}m-wavelength light and 29 mW of 700-nm-wavelength light, both fields circularly polarized at the input, gives for cesium atoms a trap depth of 2.9 mK, a coherence time of 32 ms, and a recoil-heating-limited trap lifetime of 541 s.

[1]  Ito,et al.  Laser spectroscopy of atoms guided by evanescent waves in micron-sized hollow optical fibers. , 1996, Physical review letters.

[2]  J. Knight,et al.  Phase-matched excitation of whispering-gallery-mode resonances by a fiber taper. , 1997, Optics letters.

[3]  S. Chu,et al.  Designing Neutral-Atom Nanotraps With Integrated Optical Waveguides , 2002 .

[4]  V. I. Balykin,et al.  Field intensity distributions and polarization orientations in a vacuum-clad subwavelength-diameter optical fiber , 2004 .

[5]  A. D. McLachlan,et al.  Van der Waals forces between an atom and a surface , 1964 .

[6]  Sidorov,et al.  Quantum-state-selective mirror reflection of atoms by laser light. , 1988, Physical review letters.

[7]  M. Prentiss,et al.  Substrate-based atom waveguide using guided two-color evanescent light fields , 2000 .

[8]  R. Fox,et al.  Classical Electrodynamics, 3rd ed. , 1999 .

[9]  S. Chu.  Nobel Lecture: The manipulation of neutral particles , 1998 .

[10]  K. Vahala,et al.  Highly efficient hybrid fiber taper coupled microsphere laser , 2001 .

[11]  M. Prentiss,et al.  Atom Optics with Laser Light , 1995 .

[12]  Gorachand Ghosh,et al.  Handbook of thermo-optic coefficients of optical materials with applications , 1998 .

[13]  J. Baudon,et al.  van der Waals interaction between an atom and a metallic nanowire , 2002 .

[14]  Jonathan P. Dowling,et al.  Evanescent light-wave atom mirrors, resonators, waveguides, and traps , 1996 .

[15]  Cornell,et al.  Laser-guided atoms in hollow-core optical fibers. , 1995, Physical review letters.

[16]  W. C. Martin,et al.  Handbook of Basic Atomic Spectroscopic Data , 2005 .

[17]  R. J. Cook,et al.  An electromagnetic mirror for neutral atoms , 1982 .

[18]  William J. Wadsworth,et al.  Supercontinuum generation in tapered fibers. , 2000, Optics letters.

[19]  G. G. Stokes.  "J." , 1890, The New Yale Book of Quotations.

[20]  Jacques Bures,et al.  Power density of the evanescent field in the vicinity of a tapered fiber , 1999 .

[21]  W. Phillips.  Nobel Lecture: Laser cooling and trapping of neutral atoms , 1998 .

[22]  V. I. Balykin,et al.  Atom trapping and guiding with a subwavelength-diameter optical fiber , 2004 .

[23]  S. Turner,et al.  Zero-Mode Waveguides for Single-Molecule Analysis at High Concentrations , 2003, Science.

[24]  Y. Ovchinnikov,et al.  An atomic trap based on evanescent light waves , 1991 .

[25]  Electromagnetic trapping of cold atoms , 2000 .

[26]  H. Mabuchi,et al.  Atom galleries for whispering atoms: binding atoms in stable orbits around an optical resonator. , 1994, Optics letters.

[27]  A. P. Kazantsev,et al.  Mechanical Action of Light on Atoms , 1990 .

[28]  V. Letokhov,et al.  Laser guiding of atoms in a hollow optical fiber , 1993 .

[29]  Electro-optics.  Conference on lasers and electro-optics (CLEO) , 2003 .

[30]  C. cohen-tannoudji,et al.  Nobel Lecture: Manipulating atoms with photons , 1998 .

[31]  Limin Tong,et al.  Single-mode guiding properties of subwavelength-diameter silica and silicon wire waveguides. , 2004, Optics express.