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Language：English   Publisher：INST PURE APPLIED PHYSICS  

Multireflection of cold Rb atoms occurs inside a reversed triangular hollow prism with a blue-detuned optical near field. We examine it with a probe light beam. using the frequency detuning and the diameter of an excitation light beam as parameters, In the first bounce. the number density of the reflected atoms reaches a maximum of 10(6) atom/cm(3) at a blue detuning of 0.7 GHz when the beam diameter is 4 mm. The Rb atoms repeat reflection with a period of about 15 ms and an efficiency of 83% per bounce. A cold Rb atomic beam with a high flux of 4 x 10(11) atom/(cm(2).s) can be generated through a near-Field optical funnel composed of the prism.

DOI： 10.1143/JJAP.41.6215

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Language：English   Publisher：INST PURE APPLIED PHYSICS  

We describe a slit-type detector for ground-state atoms with nanometer optical near fields. The detector with a slit width of 70 nm and a slit length of 100 mum is fabricated by processing a silicon-on-insulator wafer with photolithography and anisotropic etching. Measurement with a fiber probe of the intensity distribution on the slit reveals that the spatial resolution is 96 nm. Rubidium atoms can be selectively detected by means of two-step photoionization. The detection efficiency is estimated at 25% for Rb atoms with a mean velocity of 10 m/s. The atom detector can be used for atom deflection experiments with a fiber probe.

DOI： 10.1143/JJAP.41.1566

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DOI： 10.1143/JJAP.41.6215

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Language：English   Publisher：Institute of Electrical and Electronics Engineers Inc.  

Summary form only given. We have proposed deflection by an optical near field on a fiber probe to control atoms with high spatial accuracy. In this case, the deflection angle is estimated to be 0.1 degree for a Rb atom with an incident velocity of 10 m/s. It leads to the deviation of 10 μm from the incident axis at 1 cm. in the downstream. To detect the deflected atoms with an accuracy of 1%, we need the spatial resolution of 100 nm. However, a commercial detector such as MCP has a low resolution of 50 μm at most and the highest resolution that has been reported is 1 μm to our knowledge. In addition, these are applied to metastable atoms and have less detection efficiency for the ground state atoms we manipulate. For drastic improvement, we present here a slit-type atom detector with a nanometric lateral resolution. Since the number of atoms deflected by the optical near field is very small, it is important to detect atoms with high efficiency. For this purpose, we use photoionization with two-color optical near fields.

DOI： 10.1109/QELS.2001.961923

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DOI： 10.1103/PhysRevA.63.013806

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Language：English   Publisher：IEEE  

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%.

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DOI： 10.1103/PhysRevA.63.013806

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Language：English   Publisher：IEEE  

A cold Rb atomic beam with a low velocity of 0.10 m/s and a dense flux of 8.3x10(12) atom.cm(2)/S can be generated from a magneto-optical trap by an atom funnel.

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Language：English   Publisher：IEEE  

We describe an atom detector with two-color optical near fields designed for deflection experiments. The sensitivity is estimated to be about 10 % for both photoionization and resonant excitation schemes using a slit-type probe.

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Language：English   Publisher：IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC  

Recent progress on application of interactions between optical near-field and nanoscale materials and atoms is reviewed Photochemical vapor deposition of Zn dots and lines with the size of sub-100 nm has been realized by using an ultraviolet optical near field. Deposition of nanoscale ZnO is also revealed Manipulation of atoms is then described to control the thermal motion of atoms in high vacuum. Experimental and theoretical results of manipulation by rising optical near field generated on a prism surface, hollow fiber and fiber probe are presented. Finally quantum theoretical treatment of optical near field is given.

DOI： 10.1109/5.883321

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DOI： 10.1143/JJAP.39.6737

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DOI： 10.1143/JJAP.39.6737

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Language：English   Publisher：SPIE-INT SOC OPTICAL ENGINEERING  

We present a new scheme of atom manipulation by means of a sharpened optical fiber with near-field light. In particular, we discuss the feasibility of deflecting and trapping Rb atoms. The optical potential produced by the dipole force is estimated from numerical calculations based on the Yukawa-type intensity distribution. We show that a slow Rb atom can be deflected at a large deflection angle. A static atom trap can be made near the tip of a sharpened fiber. A cold Rb atom is captured at the minimum of the trap potential composed of the repulsive optical potential and the attractive van der Waals potential. A spatial intensity distribution of an optical near field produced near the tip of a protrusion-type fiber is measured in the fiber-to-probe configuration with a shear-force technique. We also describe an atom funnel to form a cold atomic beam required for the near-field light manipulation.

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Language：English   Publisher：ELSEVIER SCIENCE BV  

This work presents a new way useful for guiding of cold atoms with a hollow optical fiber escorted by blue-detuned evanescent light. To induce an atomic mirror-tunnel, we couple a guide-laser beam via total internal reflection from the side to the core of a hollow fiber with a facet ground at an angle of 45 degrees. The guiding of Rb atoms is demonstrated with complementary detection by means of surface-ionization and two-step photoionization. The efficiency of the lateral light-coupling is also estimated from both experiment and numerical analysis. (C) 1997 Elsevier Science B.V.

DOI： 10.1016/S0030-4018(97)00217-4

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Language：English   Publisher：ELSEVIER SCIENCE BV  

This work presents a new way useful for guiding of cold atoms with a hollow optical fiber escorted by blue-detuned evanescent light. To induce an atomic mirror-tunnel, we couple a guide-laser beam via total internal reflection from the side to the core of a hollow fiber with a facet ground at an angle of 45 degrees. The guiding of Rb atoms is demonstrated with complementary detection by means of surface-ionization and two-step photoionization. The efficiency of the lateral light-coupling is also estimated from both experiment and numerical analysis. (C) 1997 Elsevier Science B.V.

DOI： 10.1016/S0030-4018(97)00217-4

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DOI： 10.1063/1.118901

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Language：Japanese   Publisher：The Laser Society of Japan  

Optical near field realizes the precise control of atomic motion. As the first step, guiding of atoms through micron-sized hollow optical fiber is demonstrated. The two-step laser-photoionization spectroscopy shows the frequency dispersion properties of dipole interaction between atoms and optical near field. The species- and state-selective guidance is applied to in-line spatial separation of two stable Rb isotopes. In addition, the cavity QED (Quantum Electrodynamics) effect inside a dielectric cylinder is observed for the first time. The atom fiber has the faculty of carrying atoms to an arbitrary point over a long distance and then is useful as a novel scheme of optically controlled atomic deposition. The feasibility of creating dot-shaped nano-scale structures is illustrated through measurement of spatial distribution of the guided atom flux. Finally, a method of manipulating atoms beyond the diffraction limit of light waves is presented including sharpened optical fibers and an atomic funnel with optical near field.

DOI： 10.2184/lsj.25.682

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DOI： 10.1103/PhysRevA.56.712

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DOI： 10.1063/1.118901

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Language：Japanese   Publisher：東京化学同人  

CiNii Books

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DOI： 10.1103/PhysRevA.56.712

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Language：English   Publisher：SPIE - INT SOC OPTICAL ENGINEERING  

We report the recent progress of the experiments on guiding atoms by evanescent waves in micron-sized hollow optical fibers. The lateral manipulation accuracy is enhanced up to 1 micron with a large increase of more than 50 times on the guided atom flux. Moreover, the frequency tuning eanbles the fine control of the guided flux with a numerical accuracy of 10 atom/s. The atom-guidance scheme is applied to in-line isotope separation on rubidium atoms and measurement of the cavity quantum electrodynamic effect in a cylindrical dielectric. In addition, the feasibility of fabricating micron-sized structures with nanometric depth is discussed including the manipulation of a small number of laser-cooled atoms.

DOI： 10.1117/12.273749

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Language：English   Publisher：SPIE - INT SOC OPTICAL ENGINEERING  

We report the recent progress of the experiments on guiding atoms by evanescent waves in micron-sized hollow optical fibers. The lateral manipulation accuracy is enhanced up to 1 micron with a large increase of more than 50 times on the guided atom flux. Moreover, the frequency tuning eanbles the fine control of the guided flux with a numerical accuracy of 10 atom/s. The atom-guidance scheme is applied to in-line isotope separation on rubidium atoms and measurement of the cavity quantum electrodynamic effect in a cylindrical dielectric. In addition, the feasibility of fabricating micron-sized structures with nanometric depth is discussed including the manipulation of a small number of laser-cooled atoms.

DOI： 10.1117/12.273749

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DOI： 10.1103/PhysRevLett.76.4500

PubMed

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Language：Japanese  

CiNii Books

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DOI： 10.1103/PhysRevLett.76.4500

PubMed

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Language：English   Publisher：ELSEVIER SCIENCE BV  

An atomic waveguide made by a cylindrical-core hollow fiber is described using numerical analyses in the weakly guiding approximation, We describe a potential barrier made up of the optical potential due to evanescent waves and the attractive potential due to cavity QED effects. The feasibility of atomic guidance experiments with a Rb beam is discussed in terms of an evaluation of the potential barrier including interference effects.

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Language：English   Publisher：ELSEVIER SCIENCE BV  

An atomic waveguide made by a cylindrical-core hollow fiber is described using numerical analyses in the weakly guiding approximation, We describe a potential barrier made up of the optical potential due to evanescent waves and the attractive potential due to cavity QED effects. The feasibility of atomic guidance experiments with a Rb beam is discussed in terms of an evaluation of the potential barrier including interference effects.

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Language：English   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

We describe a practical atomic waveguide using a cylindrical-core hollow fiber. Theoretical analyses of propagating field modes are presented for a multimode fiber. An evanescent wave leaked out to the hollow region is shown to produce a deep optical potential enough to guide atoms with low coupling laser power under an optimal blue-detuning determined by fiber parameters, exciting mode and azimuthal angle. The excitation of an HE(11) mode required for stable atomic guidance in the multimode hollow fiber is experimentally realized with the power-coupling efficiency of more than 10%.

DOI： 10.1016/0030-4018(95)00003-Q

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Language：English   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

We describe a practical atomic waveguide using a cylindrical-core hollow fiber. Theoretical analyses of propagating field modes are presented for a multimode fiber. An evanescent wave leaked out to the hollow region is shown to produce a deep optical potential enough to guide atoms with low coupling laser power under an optimal blue-detuning determined by fiber parameters, exciting mode and azimuthal angle. The excitation of an HE(11) mode required for stable atomic guidance in the multimode hollow fiber is experimentally realized with the power-coupling efficiency of more than 10%.

DOI： 10.1016/0030-4018(95)00003-Q

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Language：English   Publisher：PHYSICAL SOC JAPAN  

We propose an efficient method of collisional transfer of transverse magnetic moment between different kinds of atoms using the spin-locking technique. Demonstrating experiments with a rotating or an oscillating rf field are carried out on a Rb-85-Cs-133 vapor, and the transfer of a large amount of the transverse magnetic moment is observed when the amplitude H-1 of the rf field is comparable to the static magnetic field strength H-0. The H-1-dependence of the transfer, in the case of the oscillating rf field, is not simple, because of the Bloch-Siegert shift and associated resonance effects. The transfer of the transverse magnetic moment under the strong rf field is numerically analyzed with the Bloch equations for Rb-85 and Cs-133 coupled through spin-exchange collisions.

DOI： 10.1143/JPSJ.63.1337

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Language：English   Publisher：PHYSICAL SOC JAPAN  

We propose an efficient method of collisional transfer of transverse magnetic moment between different kinds of atoms using the spin-locking technique. Demonstrating experiments with a rotating or an oscillating rf field are carried out on a Rb-85-Cs-133 vapor, and the transfer of a large amount of the transverse magnetic moment is observed when the amplitude H-1 of the rf field is comparable to the static magnetic field strength H-0. The H-1-dependence of the transfer, in the case of the oscillating rf field, is not simple, because of the Bloch-Siegert shift and associated resonance effects. The transfer of the transverse magnetic moment under the strong rf field is numerically analyzed with the Bloch equations for Rb-85 and Cs-133 coupled through spin-exchange collisions.

DOI： 10.1143/JPSJ.63.1337

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DOI： 10.1143/JPSJ.62.1951

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DOI： 10.1143/JPSJ.62.1951

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