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Masri G, Shahal S, Klein A, Duadi H, Fridman M. Polarization dependence of asymmetric off-resonance long period fiber gratings. OPTICS EXPRESS 2016; 24:29843-29851. [PMID: 28059370 DOI: 10.1364/oe.24.029843] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We present the polarization dependence of strong asymmetric long period fiber gratings written on tapered fibers. We found that for off-resonance conditions the spectral response and the output mode strongly depend on the input state of polarization. We utilize this dependence to obtain a mode selective device and demonstrate radially polarized and azimuthally polarized fiber lasers based on these asymmetric long period fiber gratings.
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Wang PX, Wei Q, Cai P, Wang JX, Ho YK. Neutral particles pushed or pulled by laser pulses. OPTICS LETTERS 2016; 41:230-233. [PMID: 26766681 DOI: 10.1364/ol.41.000230] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Acceleration of neutral particles is of great importance in many areas, such as controlled chemical reactions, atomic nanofabrication, and atom optics. Recent experimental studies have shown that pulsed lasers can be used to push neutral Rydberg atoms forward [Nature 461, 1261 (2009)10.1038/nature08481; Nat. Photonics 6, 386 (2012)10.1038/nphoton.2012.87]. Our simulation shows that pulsed lasers can also be used to pull Rydberg atoms back toward a light source. In particular, we proposed a method of using two laser pulses on a neutral atom, then selective operations on the neutral atom (pushing or pulling) can be performed by adjusting the delay time between the two laser pulses.
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He Y, Liu Z, Liu Y, Zhou J, Ke Y, Luo H, Wen S. Higher-order laser mode converters with dielectric metasurfaces. OPTICS LETTERS 2015; 40:5506-5509. [PMID: 26625037 DOI: 10.1364/ol.40.005506] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
A simple and compact converter based on the dielectric metasurface is proposed for the transformation of Gaussian mode to Hermite-Gaussian and Laguerre-Gaussian modes. We establish the relationship between the phase of a desired mode and the local orientation of the optical axis based on the evolution of Pancharatnam-Berry phase on Poincaré sphere. By controlling the local orientation of the optical axis in the dielectric metasurface, we can achieve any desired higher-order laser mode.
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Wong LJ, Kärtner FX. Direct acceleration of an electron in infinite vacuum by a pulsed radially-polarized laser beam. OPTICS EXPRESS 2010; 18:25035-25051. [PMID: 21164849 DOI: 10.1364/oe.18.025035] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We study the direct acceleration of a free electron in infinite vacuum along the axis of a pulsed radially-polarized laser beam. We find that net energy transfer from laser pulse to electron is maximized with the tightest focusing. We show that the net energy gain of an electron initially moving at a relativistic velocity may exceed more than half the theoretical limit of energy transfer, which is not possible with an initially stationary electron in the parameter space studied. We determine and analyze the power scaling of maximum energy gain, extending our study to include a relatively unexplored regime of low powers and revealing that substantial acceleration is already possible without the use of petawatt peak-power laser technology.
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Affiliation(s)
- Liang Jie Wong
- Department of Electrical Engineering and Computer Science and Research Laboratory of Electronics, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA.
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Fridman M, Nixon M, Grinvald E, Davidson N, Friesem AA. Real-time measurement of unique space-variant polarizations. OPTICS EXPRESS 2010; 18:10805-10812. [PMID: 20588934 DOI: 10.1364/oe.18.010805] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
A configuration for real-time measurement of unique, space-variant, polarizations is presented. The experimental results reveal that the full state of polarization at each location within the beam can be accurately obtained every 10 msec, limited only by the camera frame rate. We also present a more compact configuration which can be modified to determine the real-time wavelength variant polarization measurements.
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Affiliation(s)
- Moti Fridman
- Department of complex systems, Weizmann institute of science, Rehovot, Israel.
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Dehez H, Piché M, De Koninck Y. Enhanced resolution in two-photon imaging using a TM(01) laser beam at a dielectric interface. OPTICS LETTERS 2009; 34:3601-3603. [PMID: 19953133 DOI: 10.1364/ol.34.003601] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We have experimentally demonstrated that the resolution of a commercial two-photon microscope is improved using a TM(01) laser beam. With a water immersion objective having a 1.2 NA, the measured point- spread function has an area of 0.15lambda(2). We used a plane interface between dielectrics instead of an annular aperture to increase the relative contribution of the longitudinal field of the TM(01) laser beam. The results are in agreement with the vectorial diffraction theory established by Richards and Wolf [Proc. R. Soc. Lond. A253, 358 (1959)]. The TM(01) laser beam was produced with a quadrant of half-wave plates. We have also used the same mode converter to generate a TE(01) laser beam with a zero at the beam center.
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Affiliation(s)
- Harold Dehez
- Centre d'Optique Photonique et Laser, Université Laval, 2375 de la Terrasse, Québec, Québec G1V 0A6, Canada.
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Ishaaya AA, Hensley CJ, Shim B, Schrauth S, Koch KW, Gaeta AL. Highly-efficient coupling of linearly- and radially-polarized femtosecond pulses in hollow-core photonic band-gap fibers. OPTICS EXPRESS 2009; 17:18630-18637. [PMID: 20372594 DOI: 10.1364/oe.17.018630] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
We demonstrate extremely efficient excitation of linearly-, radially-, and azimuthally-polarized modes in a hollow-core photonic band-gap fiber with femtosecond laser pulses. We achieve coupling efficiencies as high as 98% with linearly polarized input Gaussian beams and with high-power pulses we obtain peak intensities greater than 10(14) W/cm(2) inside and transmitted through the fiber. With radially polarized pulses, we achieve 91% total transmission through the fiber while maintaining the polarization state. Alternatively with azimuthally-polarized pulses, the mode is degraded in the fiber, and the pure polarization state is not maintained.
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Affiliation(s)
- Amiel A Ishaaya
- Department of Electrical and Computer Engineering, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel.
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Ishaaya AA, Vuong LT, Grow TD, Gaeta AL. Self-focusing dynamics of polarization vortices in Kerr media. OPTICS LETTERS 2008; 33:13-15. [PMID: 18157242 DOI: 10.1364/ol.33.000013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
We investigate numerically and experimentally the spatial collapse dynamics and polarization stability of radially and azimuthally polarized vortex beams in pure Kerr medium. These beams are unstable to azimuthal modulation instabilities and break up into distinct collapsing filaments. The polarization of the filaments is primarily linear with weak circular components at the filaments' boundaries. This unique hybrid linear-circular polarization collapse pattern persists to advanced stages of collapse and appears to be a general feature of beams with spatially variant linear polarization.
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Affiliation(s)
- Amiel A Ishaaya
- School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, USA.
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Varin C, Piché M. Relativistic attosecond electron pulses from a free-space laser-acceleration scheme. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2006; 74:045602. [PMID: 17155125 DOI: 10.1103/physreve.74.045602] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2005] [Revised: 02/01/2006] [Indexed: 05/12/2023]
Abstract
In this paper we describe how relativistic attosecond electron pulses could be produced in free space by ultrafast and ultraintense transverse magnetic (TM) laser beams. Numerical solutions of the time-dependent three-dimensional Maxwell-Lorentz equations reveal that electrons initially at rest at the waist of a multi-TW pulsed TM01 laser beam can be accelerated to multi-MeV energies. The use of a few-cycle laser beam and a compact initial electron cloud forces the particles to effectively interact with a single half-cycle of the laser field and form a pulse of attosecond duration.
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Affiliation(s)
- Charles Varin
- Centre d'optique, photonique et laser, Université Laval, Québec, Qc, Canada, G1K 7P4.
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Wang G, Webb JF. Calculation of electromagnetic field components for a fundamental Gaussian beam. Phys Rev E 2005; 72:046501. [PMID: 16383546 DOI: 10.1103/physreve.72.046501] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2005] [Revised: 07/11/2005] [Indexed: 11/07/2022]
Abstract
Using a perturbative method, we carefully calculate seventh- and ninth-order expressions for electromagnetic field components for a fundamental Gaussian beam (i.e., a focused TEM00 mode laser beam) propagating in the medium analogous to vacuum. The interaction of a single electron and a focused laser pulse in vacuum has a promising application in the design of a powerful electron accelerator which could compete with the traditional ones. For this, ninth-order accuracy in the expansion describing the focused laser beam is required. When the vector potential corresponds to polarization along the direction of propagation, the number of electromagnetic field components can be reduced from 5 or 6 to 3. Furthermore, we find two rules obeyed by all orders of the vector potential, which greatly simplify the calculation procedure of the vector potential order by order, and make it possible to investigate the behavior of high orders.
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Affiliation(s)
- Guozhong Wang
- Department of Physics, Wenzhou Normal College, Wenzhou 325027, People's Republic of China
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Varin C, Piché M, Porras MA. Acceleration of electrons from rest to GeV energies by ultrashort transverse magnetic laser pulses in free space. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2005; 71:026603. [PMID: 15783437 DOI: 10.1103/physreve.71.026603] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2004] [Indexed: 05/24/2023]
Abstract
In this paper we describe a laser acceleration scheme where an electron is accelerated from rest to GeV energies by the longitudinal electric field of an ultrashort transverse magnetic ( TM01 ) optical pulse. The on-axis longitudinal electric field of the pulse is obtained from the free-space divergence equation beyond the so-called slowly-varying-envelope approximation. The instantaneous electron dynamics is studied; numerical simulations predict net energy gains in the GeV range for laser intensities reaching 10(22) W/ cm(2) .
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Affiliation(s)
- Charles Varin
- Centre d'Optique, Photonique et Laser, Université Laval, Sainte-Foy, Québec, Canada G1K 7P4.
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Novotny L, Beversluis MR, Youngworth KS, Brown TG. Longitudinal field modes probed by single molecules. PHYSICAL REVIEW LETTERS 2001; 86:5251-5254. [PMID: 11384470 DOI: 10.1103/physrevlett.86.5251] [Citation(s) in RCA: 274] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2001] [Indexed: 05/23/2023]
Abstract
We demonstrate that a strong longitudinal, nonpropagating field is generated at the focus of a radially polarized beam mode. This field is localized in space and its energy density exceeds the energy density of the transverse field by more than a factor of 2. Single molecules with fixed absorption dipole moments are used to probe the longitudinal field. Vice versa, it is demonstrated that orientations of single molecules are efficiently mapped out in three dimensions by using a radially polarized beam as the excitation source. We also show that there is no momentum or energy transport associated with the longitudinal field.
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Affiliation(s)
- L Novotny
- The Institute of Optics, University of Rochester, Rochester, New York 14627, USA.
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Rau B, Tajima T, Hojo H. Rau, tajima, and hojo reply:. PHYSICAL REVIEW LETTERS 2000; 84:3211. [PMID: 11019051 DOI: 10.1103/physrevlett.84.3211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/1999] [Indexed: 05/23/2023]
Affiliation(s)
- B Rau
- Department of Engineering Physics and Mathematics Helsinki University of Technology02015 HUT, Finland
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Hafizi B, Ganguly AK, Ting A, Moore CI, Sprangle P. Analysis of Gaussian beam and Bessel beam driven laser accelerators. PHYSICAL REVIEW. E, STATISTICAL PHYSICS, PLASMAS, FLUIDS, AND RELATED INTERDISCIPLINARY TOPICS 1999; 60:4779-92. [PMID: 11970344 DOI: 10.1103/physreve.60.4779] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/1999] [Indexed: 04/18/2023]
Abstract
This paper presents a comparison of Gaussian and Bessel beam driven laser accelerators. The emphasis is on the vacuum beat wave accelerator (VBWA), employing two laser beams of differing wavelengths to impart a net acceleration to particles. Generation of Bessel beams by means of circular slits, holographic optical elements, and axicons is outlined and the image space fields are determined by making use of Huygens' principle. Bessel beams-like Gaussian beams-experience a Guoy phase shift in the vicinity of a focal region, resulting in a phase velocity that exceeds c, the speed of light in vacuo. In the VBWA, by appropriate choice of parameters, the Guoy phases of the laser beams cancel out and the beat wave phase velocity equals c. The particle energy gain and beam quality are determined by making use of an analytical model as well as simulations. The analytical model--including the v x B interaction--predicts that for equal laser powers Gaussian and Bessel beams lead to identical energy gains. However, three-dimensional, finite-emittance simulations, allowing for detuning, transverse displacements, and including all the electromagnetic field components, show that the energy gain of a Gaussian beam driven VBWA exceeds that of a Bessel beam driven VBWA by a factor of 2-3. The particle beam emerging from the interaction is azimuthally symmetric and collimated, with a relatively small angular divergence. A table summarizing the ratios of final energies, acceleration lengths, and gradients for a number of acceleration mechanisms is given.
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Affiliation(s)
- B Hafizi
- Omega-P, Inc., P.O. Box 202008, New Haven, CT 06520-2008, USA
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Novotny L, Sánchez EJ, Sunney Xie X. Near-field optical imaging using metal tips illuminated by higher-order Hermite–Gaussian beams. Ultramicroscopy 1998. [DOI: 10.1016/s0304-3991(97)00077-6] [Citation(s) in RCA: 152] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Sprangle P, Esarey E, Krall J. Self-guiding and stability of intense optical beams in gases undergoing ionization. PHYSICAL REVIEW. E, STATISTICAL PHYSICS, PLASMAS, FLUIDS, AND RELATED INTERDISCIPLINARY TOPICS 1996; 54:4211-4232. [PMID: 9965570 DOI: 10.1103/physreve.54.4211] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Esarey E, Sprangle P, Krall J. Laser acceleration of electrons in vacuum. PHYSICAL REVIEW. E, STATISTICAL PHYSICS, PLASMAS, FLUIDS, AND RELATED INTERDISCIPLINARY TOPICS 1995; 52:5443-5453. [PMID: 9964041 DOI: 10.1103/physreve.52.5443] [Citation(s) in RCA: 261] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Feng L, Ho YK. Net electron acceleration by a strong laser field and a rf wave. PHYSICAL REVIEW. E, STATISTICAL PHYSICS, PLASMAS, FLUIDS, AND RELATED INTERDISCIPLINARY TOPICS 1994; 49:740-744. [PMID: 9961267 DOI: 10.1103/physreve.49.740] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Liu H, Neil GR. Laser-powered beam conditioner for free-electron lasers and synchrotrons. PHYSICAL REVIEW LETTERS 1993; 70:3557-3560. [PMID: 10053904 DOI: 10.1103/physrevlett.70.3557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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