Bulletin of the American Physical Society
APS March Meeting 2014
Volume 59, Number 1
Monday–Friday, March 3–7, 2014; Denver, Colorado
Session Z36: Technological Applications in AMO Physics |
Hide Abstracts |
Sponsoring Units: DAMOP Chair: Andreas Nunnenkamp, University of Basel Room: 703 |
Friday, March 7, 2014 11:15AM - 11:27AM |
Z36.00001: Imaging atoms from resonance fluorescence spectrum beyond the diffraction limit Zeyang Liao, Mohammad Al-Amri, M. Suhail Zubairy We calculate the resonance fluorescence spectrum of a linear chain of two-level atoms driven by a gradient coherent laser field. The result shows that we can determine the positions of atoms from the spectrum even when the atoms locate within subwavelength range and the dipole-dipole interaction is significant. This far-field resonance fluorescence localization microscopy method does not require point-by-point scanning and it may be more time-efficient. We also give a possible scheme to extract the position information in an extended region without requiring more peak power of laser. We also briefly discuss how to do a 2D imaging based on our scheme. [Preview Abstract] |
Friday, March 7, 2014 11:27AM - 11:39AM |
Z36.00002: Compton Scattering with a Vortex Light Beam Mazen Nairat, David Voelz The Compton effect is applied to a vortex light beam. A photon in a vortex beam possesses spin angular momentum associated with the polarization and orbital angular momentum that consists of two orthogonal components: azimuthal and axial. The azimuthal part is directly proportional to the axial part. This study considers inelastic collision of a photon possessing angular momentum with a free electron. The conservation of angular momentum as well as total energy is applied to the photon-electron system to generalize the Compton scattering model. We describe the momentum exchange and characterize the Compton effect beyond the well-known photon wavelength shift to include other parameters such as the radius of gyration. Our analysis suggests that upon an exchange of angular momentum with an electron, it is possible for the scattered photon to have no wavelength to shift. [Preview Abstract] |
Friday, March 7, 2014 11:39AM - 11:51AM |
Z36.00003: Diffraction in time: An exactly solvable model Arseni Goussev In optics, diffraction is typically portrayed as deflection of light incident upon an obstacle with sharp boundaries, that can not be accounted for by reflection or refraction. Interestingly, quantum mechanics allows for an additional, intrinsically time-dependent manifestation of the phenomenon: Owing to the dispersive nature of quantum matter waves, sudden changes in boundary conditions may cause the particle wave function to develop interference fringes akin to those in stationary (optical) diffraction problems. This phenomenon, pioneered in 1952 by Moshinsky [{\it Phys. Rev.} {\bf 88}, 625 (1952)] and presently referred to as ``diffraction in time,'' is at the heart of a vibrant area of experimental and theoretical research concerned with quantum transients. In my talk, I will introduce a new versatile exactly-solvable model of diffraction in time. The model describes dynamics of a quantum particle in the presence of an absorbing time-dependent barrier, and enables a quantitative description of diffraction and interference patterns in a large variety of setups.\\[4pt] [1] A. Goussev, {\it Phys. Rev. A} {\bf 87}, 053621 (2013).\\[0pt] [2] A. Goussev, {\it Phys. Rev. A} {\bf 85}, 013626 (2012). [Preview Abstract] |
Friday, March 7, 2014 11:51AM - 12:03PM |
Z36.00004: Projection on tilted screens using a phase only spatial light modulator Javad R. Gatabi, Bill Mckenna, Kumar Pandey, Dan Tamir, Wilhelmus J. Geerts We are developing a new laser lithography exposure tool for use on non-flat substrates. Such a tool does currently not exists as commercial equipment used in the electronic industry uses high numerical aperture (NA) lenses to create patterns with critical dimensions down to 22 nm on very flat substrates ($+$/- 100 nm). The ability to pattern thin films on top of curved substrates with large topography differences allows for the development of new products and devices. We investigated the use of a phase only spatial modulator to project images on inclined and curved surfaces in such exposure equipment. Starting from the Raleigh-Sommerfeld diffraction equation, expressions for the diffraction between titled surfaces were derived. These expressions were used in an iterative algorithm to determine the modulator phase pattern required for a proper projection of an image on a curved surface. An approach similar to that of Gerchberg and Saxton [1] was followed. The algorithm was implemented using a Holoeye LCD phase only modulator. It was shown to be stable and converging for simple binary test patterns. A similar approach may be used for projection from a tilted surface to a curved surface. \\[4pt] [1] R. W. Gerchberg, W. O. Saxton, OPTIK, Vol. 35 (No.2) 237-246 (1972). [Preview Abstract] |
Friday, March 7, 2014 12:03PM - 12:15PM |
Z36.00005: Compressive sensing for spatial and spectral flame diagnostics David Starling, Joseph Ranalli Compressive sensing has been a valuable resource for use in quantum imaging, low light level depth mapping of natural scenes, object tracking and even for the improvement of miniature spectrometers via post processing. Experimentally, many optical compressive sensing techniques utilize a single pixel camera composed of a digital micromirror device or spatial light modulator coupled to one shot-noise limited detector. This method has the advantages of fast acquisition time and high signal to noise ratio. One currently unexplored area of study is the use of these techniques in the context of flame diagnostics. Optical diagnostics are employed for a variety of purposes in flames, including imaging of the heat release region (via chemiluminescence) and spatially resolved species and temperature measurement (via spontaneous Raman scattering). Compressive sensing has a dual role in this field, where the signals of interest are generally sparse and the mean photon flux is very low at the appropriate wavelengths. We show here that compressive sensing is beneficial in particular for the study of laminar, steady flames using Raman spectroscopy and flame chemiluminescence imaging, without the use of intensified CCDs, commercial spectrometers or high intensity pulse lasers. We present results from a theoretical study with experimental data to follow. [Preview Abstract] |
Friday, March 7, 2014 12:15PM - 12:27PM |
Z36.00006: Reflective Optical and Microwave Limiters based on Non-Linear Localized Modes Eleana Makri, Hamidreza Ramezani, Tsampikos Kottos, Ilya Vitebskiy A limiter is a structure that controls signal transport by allowing the transmission of low intensity signals while blocking signals with excessively high intensity. Existing designs lead to the absorption of excessive high intensity which can cause their overheating and eventually their (self-)destruction. We introduce the concept of {\it reflective limiter} which is based on resonance transmission via a non-linear localized mode. Such a limiter does not absorb the high level radiation, but rather reflects it back to space. Importantly, the total reflection occurs within a broad frequency range and for any direction of incidence. The proposed concept can be applied to optical and microwave frequencies. [Preview Abstract] |
Friday, March 7, 2014 12:27PM - 12:39PM |
Z36.00007: ABSTRACT WITHDRAWN |
Friday, March 7, 2014 12:39PM - 12:51PM |
Z36.00008: ABSTRACT MOVED TO A34.00013 |
Friday, March 7, 2014 12:51PM - 1:03PM |
Z36.00009: Regularization of spectral singularities in a PT-symmetric system with saturable nonlinearities Xuele Liu, Subhasish Dutta Gupta, Girish Agarwal Spectral response of a linear PT-symmetric system is known to lead to singularities leading to infinite transmission and reflection coefficients. Near such spectral singularities (because of the infinite growth of the amplitudes) the assumption of linearity of the system breaks down, and it is necessary to incorporate a nonlinear mechanism, which could saturate the growth of the scattering amplitudes. We show that an all-order nonlinearity, such as a saturable nonlinearity, can indeed limit the infinities associated with the linear PT-symmetric systems. In the example of a quasi-one dimensional wave-guide with equal loss and gain segments, we demonstrate this regularisation. Our numerical simulation is based on the exact Helmholtz equation with the saturable gain and loss. We further present explicit numerical results to demonstrate optical diode action, whereby, light is allowed to pass only in one preferential direction, and it is blocked for the other direction. The switching and near-perfect isolation of the PT-symmetric device can find many applications in optical signal processing and chip-level integration. [Preview Abstract] |
Friday, March 7, 2014 1:03PM - 1:15PM |
Z36.00010: A Clifford Algebra Description of Polarization Optics David Yevick, George Soliman The polarization changes induced by optical components are represented as Clifford algebra transformations. This yields a unified formalism for polarized and partially polarized light and for the frequency dependence of polarization in the presence of polarization mode dispersion and polarization dependent loss. [Preview Abstract] |
Friday, March 7, 2014 1:15PM - 1:27PM |
Z36.00011: CO$_{2}$ TEA Laser-Enhanced Laser Ablation Molecular Isotopic Spectrometry (TELLAMIS) Staci R. Brown, Charlemagne A. Akpovo, Alan Ford, Kenley Herbert, Lewis Johnson Recently, it has been shown that the relative abundance of isotopes in enriched materials can be determined via laser-induced breakdown spectroscopy (LIBS) in a technique known as laser-ablation molecular isotopic spectroscopy (LAMIS). The original LAMIS work has focused on single-pulse (SP) LIBS for the excitation. However, dual-pulse (DP) LIBS reduces shot-to-shot variation and can lower detection limits of an element by about an order of magnitude or more. It also has the potential to improve the accuracy of the determination of the relative abundances of isotopes in LAMIS by minimizing the signal-to-noise ratio. In this work, a DP-LIBS technique for improving LAMIS relative-abundance information from a sample is presented. The new technique, called (TEA) Transverse-Excited breakdown in Atmosphere Laser-Enhanced Laser Ablation Molecular Isotopic Spectrometry (TELLAMIS), uses a carbon dioxide (CO$_{2})$ laser to increase the breakdown emission from LIBS in the LAMIS method. This technique is demonstrated on a collection of relative abundance isotopes of boron- 10 and boron-11 in varying concentrations in boric acid. Least-squares fitting to theoretical models are used to deduce plasma parameters and understand reproducibility of results. [Preview Abstract] |
Friday, March 7, 2014 1:27PM - 1:39PM |
Z36.00012: Ultracold Cesium source for FIB below 1nm: Milling, deposition, and lithography Ross Martin-Wells We discuss the applications, models, and apparatus for a high-brightness, low-emittance Focused Ion Beam(FIB) source from ultracold cesium atoms. We propose a system where the atoms are cooled in two Magneto-Optic Traps(MOT) and degenerate sideband cooled in an optical lattice, decreasing the temperature to 100-300nK. Temperatures in the nanokelvin regime mean that by adapting current ion lens techniques from an Liquid Metal Ion Source (LMIS) column, our cesium ion beam can be focused to $<$1 nm. The ionization process at these ultracold temperatures is studied using a Monte Carlo simulation, determining the velocity distribution of the ions. After ionization via a two-frequency excitation, the cloud is accelerated by electric fields in the same way as LMIS FIB systems. We also discuss: (1)production of a much higher current continuous wave ultracold atom source for nanofabrication and (2) the use of interferometrically stabilized optical interference masks as a system to print structures of linewidth $<$1nm by the deposition of atoms from a variety of ultracold sources. These tools could make major contributions in the fields of lithography and microscopy in nanofabrication, conducting milling operations as well as deposition and microscopy far below the photon-diffraction limit [Preview Abstract] |
Friday, March 7, 2014 1:39PM - 1:51PM |
Z36.00013: Superpositions of Free Electron Vortices and Measurement of Matter Wave Gouy Phase Benjamin McMorran, Tyler Harvey, Jordan Pierce, Martin Linck We demonstrate superpositions of free electron matter wave orbital states using nanofabricated diffraction holograms. The orbital superposition is comprised of an electron beam that is a coherent mixture of two overlapped, co-propagating vortex beam modes with different topological charge. Whereas a pure mode electron vortex beam forms an annular spot when projected onto an imaging detector, the superposition has an intensity profile that is broken into azimuthal lobes. The number of lobes is given by the absolute difference in topological charge between the two orbital components. We created superpositions of vortices with various topological charges, from $m_{\ell}$ = 0 to 15. We use these superposition states to measure the Gouy phase measurement for matter waves. We discuss the possibility of using these beams to measure magnetic fields. [Preview Abstract] |
Friday, March 7, 2014 1:51PM - 2:03PM |
Z36.00014: ABSTRACT WITHDRAWN |
Friday, March 7, 2014 2:03PM - 2:15PM |
Z36.00015: Ion Production in the Presence of Isotopes for Various Gasses Benjamin Graber, Rongjia Tao, Dong Ho Wu Gamma radiation creates ions in gasses. Since each gas has unique ionization energy, the positive and negative ion production rate will be dependent on the radiation energy. Each radioactive isotope has a characteristic gamma ray spectra. Combining these ideas, by using a few chambers containing different gasses with ion counters, one can construct a nuclear material detector that can identify an isotope. This experiment was carried out using Ar, CO2, O2, N2, regular air and humid air environments. These environments were exposed to Am, Ba, Co, Cs and Na while the positive and negative ions were counted over time. This procedure confirmed our expected result. This detection method is currently patent pending. [Preview Abstract] |
Follow Us |
Engage
Become an APS Member |
My APS
Renew Membership |
Information for |
About APSThe American Physical Society (APS) is a non-profit membership organization working to advance the knowledge of physics. |
© 2024 American Physical Society
| All rights reserved | Terms of Use
| Contact Us
Headquarters
1 Physics Ellipse, College Park, MD 20740-3844
(301) 209-3200
Editorial Office
100 Motor Pkwy, Suite 110, Hauppauge, NY 11788
(631) 591-4000
Office of Public Affairs
529 14th St NW, Suite 1050, Washington, D.C. 20045-2001
(202) 662-8700