Last week papers (18th week of 2012)

From 22 to 28 of April 2012, well it was really from 22 to 26 as I took a long weekend off the office...

Published

• "Quantum Computing with Incoherent Resources and Quantum Jumps" by  M. F. Santos et. al., Physical Review Letters 108, 170501 (2012).
  
  
  So, let us say that you have logarithmic spare time and want to make nature do computation for you. Well, Marcelo and coauthors have just show that, in principle, you just need time, patience, clickers and a way to put/remove them clickers from your open system. 


• "Optical Forces and Torques in Nonuniform Beams of Light" by D. B. Ruffner and David G. Grier, Physical Review Letters 108,  173602 (2012).
  
  
  I don't remember seeing an optical tweezer paper in PRL. The authors analyze linear and angular momentum densities of light beams to show how amplitude, phase and polarization profiles contribute to optical forces. One interesting thing they found is how the curl of the spin angular momentum can exert torque on objects without contributing to the orbital angular momentum of the beam. 


• "Equilibrium and disorder-induced behavior in quantum light–matter systems" by E. Mascarenhas et. al., New Journal of Physics 14,  043033 (2012).
  
  Coupled two-level system cavity arrays in the polaritonic regime have been proposed to realize the Bose-Hubbard model and Insulator-Superfluid transition  in the past. Now, by using a mean field approach the authors study the effects of disorder on the phases of the Jaynes-Cummings-Hubbard model and find glassy phases using entanglement measures. Interesting, ain't it?  

Preprints

• "Supermodes of Hexagonal Lattice Waveguide Arrays" by J. S. Brownless et. al., arXiv: 1204.4974v1 [quant-ph].
  
  
  A modal approach to hexagonal  photonic waveguide arrays. I'm still trying to follow it and get their results and see if it helps me solve some other waveguide lattices.


• "Relating the quantum mechanics of discrete systems
  to standard canonical quantum mechanics" by G. Hooft , arXiv: 1204.4926v1 [quant-ph].
  
  So, imagine you are working near the Planck scale and you want to see if there's something happening there, most probably you want to go from continuous to discrete modelling of the system. Well, here's an approach focused on applications to the harmonic oscillator. I need time to sit down and follow this, discrete dynamics is always interesting for me.


• "Dynamical scattering models in optomechanics: Going beyond the `coupled cavities' model" by A. Xuereb and P. Domokos  , arXiv: 1204.5301v1 [quant-ph].
  
  
  An analysis of membrane-coupled cavities from first principles. In short, we are safe using the coupled-cavities simplification if the coupling element reflectivity is not way below 50% .


• "Morse potential derived from first principles" by R. Costa Filho et. al., arXiv: 1204.5931v1 [quant-ph].
  
  I .