Browsing UMBC Physics Department by Issue Date

Now showing items 1-20 of 1756

    • Postselection-free energy-time entanglement 

      Strekalov, D. V.; Pittman, T.B.; Sergienko, A. V.; Shih, Y. H.; Kwiat, P. G. (American Physical Society (APS), 1996-07-01)
      We report a two-photon interference experiment that realizes a postselection-free test of Bell's inequality based on energy-time entanglement. In contrast with all previous experiments of this type, the employed entangled ...

    • Can Two-Photon Interference be Considered the Interference of Two Photons? 

      Pittman, T. B.; Strekalov, D. V.; Migdall, A.; Rubin, M. H.; Sergienko, A. V.; Shih, Y. H. (American Physical Society (APS), 1996-09-02)
      We report on a “postponed compensation” experiment in which the observed two-photon entangled state interference cannot be pictured in terms of the overlap of the two individual photon wave packets of a parametric ...

    • Electron-positron jets associated with the quasar 3C279 

      Wardle, J.F.C.; Homan, D.C.; Ojha, R.; Roberts, D.H. (Brandeis University, 1998)
      A long outstanding problem in extragalactic astrophysics is the composition of the relativistic jets of plasma streaming from the nuclei of quasars and active galaxies - whether it is predominantly a "normal" (electron-proton) ...

    • The optical absorption edge of diamond-like carbon: A quantum well model 

      Pelton, Matthew; O’Leary, Stephen K.; Gaspari, Franco; Zukotynski, Stefan (AIP, 1998-01-15)
      This article presents an analysis of the optical absorption edge of diamond-like carbon, based on transitions between confined electronic states in quantum wells. This theory is proposed to replace the commonly-used Tauc ...

    • Deconstructing the Affirmative Action Categories 

      La Noue, George R.; Sullivan, John C. (SAGE, 1998-04-01)
      Affirmative action preferences have traditionally benefited four racial and ethnic group categories: African Americans, Hispanics, Asian Americans, and Native Americans. These categories may be overinclusive, masking ...

    • Ultralow threshold laser using a single quantum dot and a microsphere cavity 

      Pelton, Matthew; Yamamoto, Yoshihisa (APS, 1999-03-01)
      We propose a novel semiconductor microlaser, made by capturing the light emitted from a single InAs/GaAs quantum dot in the whispering-gallery mode of a glass microsphere. We demonstrate that such an arrangement allows the ...

    • Multi-Photon Entanglement and Quantum Teleportation 

      Shih, Yanhua (U. S. Army Research Office, 1999-07-31)
      The project "Multi-Photon Entanglement and Quantum Teleportation" concerns a series of experimental and theoretical investigations on multi-photon entangled states and the applications, for example, quantum teleportation. ...

    • Regulated and Entangled Photons from a Single Quantum Dot 

      Benson, Oliver; Santori, Charles; Pelton, Matthew; Yamamoto, Yoshihisa (APS, 2000-03-13)
      We propose a new method of generating nonclassical optical field states. The method uses a semiconductor device, which consists of a single quantum dot as active medium embedded in a p- i- n junction and surrounded by a ...

    • Quantum logic using photon-exchange interactions 

      Franson, J.D.; Pittman, T.B. (OSA Publishing, 2000-05)
      Nonlinear optical effects at the two-photon level are usually negligible because of the weak electric field associated with a single photon.

    • Search for the Identification of 3EG J1835+5918: Evidence for a New Type of High-Energy Gamma-Ray Source 

      Mirabal, N.; Halpern, J. P.; Eracleous, M.; Becker, R. H. (IOP, 2000-05-10)
      The EGRET source 3EG J1835+5918 is the brightest and most accurately positioned of the as-yet unidentified high-energy γ-ray sources at high Galactic latitude (ℓ,b = 89°,25°). We present a multiwavelength study of the ...

    • GRB 991216 Joins the Jet Set: Discovery and Monitoring of its Optical Afterglow 

      Halpern, J. P.; Uglesich, R.; Mirabal, N.; Kassin, S.; Thorstensen, J.; Keel, W. C.; Diercks, A.; Bloom, J. S.; Harrison, F.; Mattox, J.; Eracleous, M. (IOP, 2000-06-15)
      The optical light curve of the energetic γ-ray burst GRB 991216 is consistent with jetlike behavior in which a power-law decay steepens from t⁻¹·²²⁺⁰·⁰⁴ at early times to t⁻¹·⁵³⁺⁰·⁰⁵ in a gradual transition at around 2 ...

    • The Antarctic Submillimeter Telescope and Remote Observatory (AST/RO) 

      Stark, Antony A.; Bally, John; Balm, Simon P.; Bania, T. M.; Bolatto, Alberto D.; Chamberlin, Richard A.; Engargiola, Gregory; Huang, Maohai; Ingalls, James G.; Jacobs, Karl; Jackson, James M.; Kooi, Jacob W.; Lane, Adair P.; Lo, K.-Y.; Marks, Rodney D.; Martin, Christopher L.; Mumma, Dennis; Ojha, Roopesh; Schieder, Rudolf; Staguhn, Johannes; Stutzki, Juergen; Walker, Christopher K.; Wilson, Robert W.; Wright, Gregory A.; Zhang, Xiaolei; Zimmermann, Peter; Zimmermann, Ruediger (IOP, 2000-12-15)
      AST/RO, a 1.7 m diameter telescope for astronomy and aeronomy studies at wavelengths between 200 and 2000 microns, was installed at the South Pole during the 1994-1995 Austral summer. The telescope operates continuously ...

    • A Neutron Star Identification for the High-Energy Gamma-Ray Source 3EG J1835+5918 Detected in the ROSAT All-Sky Survey 

      Mirabal, N.; Halpern, J. P. (IOP, 2001-01-24)
      In the error box of 3EG J1835+5918, the brightest as-yet unidentified EGRET source at intermediate Galactic latitude, we find a weak, ultrasoft X-ray source at energies E < 0.3 keV in the ROSAT All-Sky Survey. Deep optical ...

    • Synthesis and Nonlinear Optical Properties of a New Syndioregic Main-Chain Hydrazone Polymer 

      Hayden, L. Michael; Kim, Won-Kook; Chafin, Andrew P.; Lindsay, Geoffrey A. (ACS Publications, 2001-01-31)
      The synthesis of a syndioregic main-chain hydrazone nonlinear optical polymer is reported. The nonlinearity is thermally stable up to 140 °C and retains 90% of the original value even when stored at 100 °C for 100 h. The ...

    • AST/RO Observations of Atomic Carbon near the Galactic Center 

      Ojha, Roopesh; Stark, Antony A.; Hsieh, Henry H.; Lane, Adair P.; Chamberlin, Richard A.; Bania, Thomas M.; Bolatto, Alberto D.; Jackson, James M.; Wright, Gregory A. (IOP, 2001-02-10)
      We present a coarsely sampled map of the region |l| ≤ 2°, |b| ≤ 0°1 in the 492 GHz (³P₁ → ³P₀) fine-structure transition of neutral carbon, observed with the Antarctic Submillimeter Telescope and Remote Observatory (AST/RO). ...

    • Triggered single photons from a quantum dot 

      Santori, Charles; Pelton, Matthew; Solomon, Glenn; Dale, Yseulte; Yamamoto, Yoshihisa (APS, 2001-02-19)
      We demonstrate a new method for generating triggered single photons. After a laser pulse generates excitons inside a single quantum dot, electrostatic interactions between them and the resulting spectral shifts allow a ...

    • Multicolor Observations of the GRB 000926 Afterglow 

      Price, P. A.; Harrison, F. A.; Galama, T. J.; Reichart, D. E.; Axelrod, T. S.; Berger, E.; Bloom, J. S.; Busche, J.; Cline, T.; Diercks, A.; Djorgovski, S. G.; Frail, D. A.; Gal-Yam, A.; Halpern, J.; Holtzman, J. A.; Hunt, M.; Hurley, K.; Jacoby, B.; Kimble, R.; Kulkarni, S. R.; Mirabal, N.; Morrison, G.; Ofek, E.; Pevunova, O.; Sari, R.; Schmidt, B. P.; Turnshek, D.; Yost, S. (IOP, 2001-02-26)
      We present multicolor light curves of the optical afterglow of gamma-ray burst (GRB) 000926. Beginning ~1.5 days after the burst, the light curves of this GRB steepen measurably. The existence of such achromatic breaks is ...

    • Parsec-Scale Blazar Monitoring: Proper Motions 

      Homan, Daniel C.; Ojha, Roopesh; Wardle, John F. C.; Roberts, David H.; Aller, Margo F.; Aller, Hugh D.; Philip A. Hughes (IOP, 2001-03-10)
      We present proper motions obtained from a dual-frequency, six-epoch, VLBA polarization experiment monitoring a sample of 12 blazars. The observations were made at 15 and 22 GHz at bimonthly intervals over 1996. A total of ...

    • Tidal Satellite Perturbations and the Lense-Thirring Effect 

      Iorio, Lorenzo; Pavlis, Erricos C. (The Geodetic Society of Japan, 2001-03-25)

    • GRB 000418: A Hidden Jet Revealed 

      Berger, E.; Diercks, A.; Frail, D. A.; Kulkarni, S. R.; Bloom, J. S.; Sari, R.; Halpern, J.; Mirabal, N.; Taylor, G. B.; Hurley, K.; Pooley, G.; Becker, K. M.; Wagner, R. M.; Terndrup, D. M.; Statler, T.; Wik, D. R.; Mazets, E.; Cline, T. (IOP, 2001-04-05)
      We report on optical, near-infrared, and centimeter radio observations of GRB 000418 that allow us to follow the evolution of the afterglow from 2 to 200 days after the γ-ray burst (GRB). In modeling these broadband data, ...