Now showing items 1-9 of 9

    • Discrete Single-Photon Quantum Walks with Tunable Decoherence 

      Broome, M. A.; Fedrizzi, A.; Lanyon, B. P.; Kassal, Ivan; Aspuru-Guzik, Alan; White, A. G. (American Physical Society, 2010)
      Quantum walks have a host of applications, ranging from quantum computing to the simulation of biological systems. We present an intrinsically stable, deterministic implementation of discrete quantum walks with single ...
    • Environment-Assisted Quantum Transport 

      Rebentrost, Patrick; Mohseni, Masoud; Kassal, Ivan; Lloyd, Seth; Aspuru-Guzik, Alan (Institute of Physics, 2009)
      Transport phenomena at the nanoscale are of interest due to the presence of both quantum and classical behavior. In this work, we demonstrate that quantum transport efficiency can be enhanced by a dynamical interplay of ...
    • Environment-Assisted Quantum Transport in Ordered Systems 

      Kassal, Ivan; Aspuru-Guzik, Alan (IOP Publishing, 2012)
      Noise-assisted transport in quantum systems occurs when quantum time evolution and decoherence conspire to produce a transport efficiency that is higher than what would be seen in either the purely quantum or purely classical ...
    • Examination of pigments on Thai manuscripts: the first identification of copper citrate 

      Eremin, Katherine; Stenger, Jens; Huang, Jo-Fan; Aspuru-Guzik, Alan; Betley, Theodore A; Vogt, Leslie; Kassal, Ivan; Speakman, Scott; Khandekar, Narayan (Wiley-Blackwell, 2008)
      Samples from Thai manuscripts dated to the 18th to 20th century were analyzed by Raman spectroscopy and Fourier-transform infrared spectroscopy (FTIR) to determine the pigments used. This suggested a change in palette from ...
    • Polynomial-Time Quantum Algorithm for the Simulation of Chemical Dynamics 

      Kassal, Ivan; Jordan, Stephen P.; Love, Peter J.; Mohseni, Masoud; Aspuru-Guzik, Alan (National Academy of Sciences, 2008)
      The computational cost of exact methods for quantum simulation using classical computers grows exponentially with system size. As a consequence, these techniques can be applied only to small systems. By contrast, we ...
    • Preparation of Many-Body States for Quantum Simulation 

      Ward, Nicholas J.; Kassal, Ivan; Aspuru-Guzik, Alan (American Institute of Physics, 2009)
      While quantum computers are capable of simulating many quantum systems efficiently, the simulation algorithms must begin with the preparation of an appropriate initial state. We present a method for generating physically ...
    • Quantum Algorithm for Molecular Properties and Geometry Optimization 

      Kassal, Ivan; Aspuru-Guzik, Alan (American Institute of Physics, 2009)
      Quantum computers, if available, could substantially accelerate quantum simulations. We extend this result to show that the computation of molecular properties (energy derivatives) could also be sped up using quantum ...
    • Simulating Chemistry Using Quantum Computers 

      Kassal, Ivan; Whitfield, James D.; Perdomo-Ortiz, Alejandro; Yung, Man-Hong; Aspuru-Guzik, Alan (Annual Reviews, 2011)
      The difficulty of simulating quantum systems, well-known to quantum chemists, prompted the idea of quantum computation. One can avoid the steep scaling associated with the exact simulation of increasingly large quantum ...
    • Towards Quantum Chemistry on a Quantum Computer 

      Lanyon, B. P.; Whitfield, James Daniel; Gillett, G. G.; Goggin, M. E.; Almeida, M. P.; Kassal, Ivan; Biamonte, J. D.; Mohseni, Masoud; Powell, B. J.; Barbieri, M.; Aspuru-Guzik, Alan; White, Andrew G. (Nature Publishing Group, 2010)
      Exact first-principles calculations of molecular properties are currently intractable because their computational cost grows exponentially with both the number of atoms and basis set size. A solution is to move to a radically ...