Quantum annealing of a disordered magnet

  title={Quantum annealing of a disordered magnet},
  author={Brooke and Bitko and Rosenbaum and Aeppli},
  volume={284 5415},
  • Brooke, Bitko, +1 author Aeppli
  • Published 30 April 1999
  • Chemistry, Materials Science, Physics, Medicine
  • Science
Traditional simulated annealing uses thermal fluctuations for convergence in optimization problems. Quantum tunneling provides a different mechanism for moving between states, with the potential for reduced time scales. Thermal and quantum annealing are compared in a model disordered magnet, where the effects of quantum mechanics can be tuned by varying an applied magnetic field. The results indicate that quantum annealing hastens convergence to the optimum state. 
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It is concluded that, contrary to theoretical expectations, quantum transitions can be qualitatively different from thermally driven transitions in real spin glasses.
Ferromagnetism, glassiness, and metastability in a dilute dipolar-coupled magnet.
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Stochastic Relaxation, Gibbs Distributions, and the Bayesian Restoration of Images
  • S. Geman, D. Geman
  • Mathematics, Medicine
    IEEE Transactions on Pattern Analysis and Machine Intelligence
  • 1984
The analogy between images and statistical mechanics systems is made and the analogous operation under the posterior distribution yields the maximum a posteriori (MAP) estimate of the image given the degraded observations, creating a highly parallel ``relaxation'' algorithm for MAP estimation.