Now showing items 690-709 of 971

    • Quality assessment of LARES satellite ranging data 

      Pavlis, Erricos C.; Paolozzi, A.; Paris, C.; Ciufolini, I.; Sindoni, G. (IEEE\, 2015-06-05)
      LARES is an Italian Space Agency mission designed to test General Relativity in the weak field of Earth. In particular, the satellite will be able to measure frame-dragging with an accuracy of about 1%. The difficulty of ...
    • Quantifying the Impacts of Subpixel Reflectance Variability on Cloud Optical Thickness and Effective Radius Retrievals Based On High-Resolution ASTER Observations 

      Werner, F.; Zhang, Z.; Wind, G.; Miller, D. J.; Platnick, S. (American Geophysical Union, 2018-04-26)
      Recently, Zhang et al. (2016, presented a mathematical framework based on a second-order Taylor series expansion in order to quantify the plane-parallel homogeneous bias (PPHB) in cloud ...
    • Quantum and classical ergotropy from relative entropies 

      Sone, Akira; Deffner, Sebastian
      The quantum ergotropy quantifies the maximal amount of work that can be extracted from a quantum state without changing its entropy. We prove that the ergotropy can be expressed as the difference of quantum and classical ...
    • Quantum Computing Using Linear Optics 

      Pittman, Todd B.; Jacobs, Bryan C.; Franson, James D.
    • Quantum computing using single photons and the Zeno effect 

      Franson, J.D.; Jacobs, B. C.; Pittman, T.B. (American Physical Society (APS), 2004-12-01)
      We show that the quantum Zeno effect can be used to suppress the failure events that would otherwise occur in a linear optics approach to quantum computing. From a practical viewpoint, that would allow the implementation ...
    • Quantum computing, but even faster? UMBC researchers explore the possibilities with new NSF grant 

      Demond, Marlayna; Myers, Nathan
      Quantum computers have the potential to revolutionize communications, cybersecurity, and more, by dramatically speeding computation, researchers say. But as Sebastian Deffner notes, “Even quantum computing has shortcomings.”
    • Quantum Efficiency Study and Reflectivity Enhancement of Au/Bi Absorbers 

      Hummatov, R.; Adams, J. S.; Bandler, S. R.; Barlis, A.; Beaumont, S.; Chang, M. P.; Chervenak, J. A.; Datesman, A. M.; Eckart, M. E.; Finkbeiner, F. M.; Ha, J. Y.; Kelley, R. L.; Kilbourne, C. A.; Miniussi, A. R.; Porter, F. S.; Sadleir, J. E.; Sakai, K.; Smith, S. J.; Wakeham, N.; Wassell, E. J.; Wollack, E. J. (Springer Nature Switzerland AG., 2020-03-07)
      X-ray absorbers of the X-ray Integral Field Unit (X-IFU) microcalorimeters are required to provide high quantum efficiency (QE) for incident X-rays and high reflectivity to longer wavelength radiation. The thickness of the ...
    • Quantum entropy production in phase space 

      Deffner, Sebastian (IOP, 2013-08-12)
      A fluctuation theorem for the nonequilibrium entropy production in quantum phase space is derived, which enables the consistent thermodynamic description of arbitrary quantum systems, open and closed. The new treatment ...
    • Quantum Error Correction using Linear Optics 

      Pittman, T.B.; Jacobs, B. C.; Franson, J.D. (OSA Publishing, 2005-10)
      We describe a laboratory demonstration of a quantum error correction procedure that can correct intrinsic measurement errors in linear-optics quantum gates. The procedure involved a photonic two-qubit encoding and fast ...
    • Quantum fluctuation theorem for error diagnostics in quantum annealers 

      Gardas, Bartłomiej; Deffner, Sebastian (Springer Nature, 2018-11-21)
      Near term quantum hardware promises unprecedented computational advantage. Crucial in its development is the characterization and minimization of computational errors. We propose the use of the quantum fluctuation theorem ...
    • Quantum fluctuation theorem to benchmark quantum annealers 

      Gardas, Bartlomiej; Deffner, Sebstian (2018)
      Near term quantum hardware promises unprecedented computational advantage. Crucial in its development is the characterization and minimization of computational errors. We propose the use of the quantum fluctuation theorem ...
    • Quantum fluctuation theorems in the strong damping limit 

      Deffner, S.; Brunner, M.; Lutz, E. (IOP, 2011-04-21)
      We consider a driven quantum particle in the strong friction regime described by the quantum Smoluchowski equation. We derive Crooks and Jarzynski type relations for the reduced quantum system by properly generalizing the ...
    • Quantum Heat Engines with Singular Interactions 

      Myers, Nathan; McCready, Jacob; Deffner, Sebastian (MDPI, 2021-05-31)
      By harnessing quantum phenomena, quantum devices have the potential to outperform their classical counterparts. Here, we examine using wave function symmetry as a resource to enhance the performance of a quantum Otto engine. ...
    • Quantum logic operations in optical fibers 

      Jacobs, B. C.; Fitch, M. J.; Pittman, T.B.; Franson, J.D. (OSA Publishing, 2003-06)
      We have recently demonstrated several probabilistic quantum logic operations using linear optics and post selection. Here we show how the fidelity of these devices can be increased using fibers to reduce optical mode ...
    • Quantum logic operations using linear optical elements 

      Franson, J.D.; Jacobs, B. C.; Pittman, T.B. (OSA Publishing, 2002-08)
      Knill, Laflamme, and Milburn [1] have shown that probabilistic quantum logic operations can be implemented using linear optical elements, such as beam splitters and phase shifters, additional photons (ancilla) and ...
    • 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.
    • Quantum relays and noise suppression using linear optics 

      Jacobs, B. C.; Pittman, T.B.; Franson, J.D.
      Probabilistic quantum nondemolition (QND) measurements can be performed using linear optics and postselection. Here we show how QND devices of this kind can be used in a straightforward way to implement a quantum relay, ...
    • Quantum scrambling and the growth of mutual information 

      Touil, Akram; Deffner, Sebastian (2020-02-07)
      Quantum information scrambling refers to the loss of local recoverability of quantum information, which has found widespread attention from high energy physics to quantum computing. In the present analysis we propose a ...
    • Quantum Speed Limit for Non-Markovian Dynamics 

      Deffner, Sebastian; Lutz, Eric (American Physical Society (APS), 2013-07-03)
      We derive a Margolus-Levitin-type bound on the minimal evolution time of an arbitrarily driven open quantum system. We express this quantum speed limit time in terms of the operator norm of the nonunitary generator of the ...