Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Negative kinetic energy in Bose Hubbard mode?

  1. Jul 12, 2013 #1
    Too familiar with Bose Hubbard model, but suddenly got stuck by a simple question: Why is the kinetic term (to be precise should be single body part) negative?
     
  2. jcsd
  3. Jul 12, 2013 #2

    fzero

    User Avatar
    Science Advisor
    Homework Helper
    Gold Member

    The hopping term is not just the kinetic energy, but also includes the interaction of the particles with the lattice. If the interaction between the particles and the lattice sites is attractive, then often the energy spectrum will contain negative energy bound states (ignoring the other interactions, these are just the analogue of electrons being bound in atoms). Note that the hopping parameter (usually called ##t##) must still be specified. The - sign is usually chosen in the expectation that ##t>0##, but for a specific system, it might not be so.
     
  4. Jul 14, 2013 #3
    Thank you for your response! Can you show one example, in which ##t>0##?
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Negative kinetic energy in Bose Hubbard mode?
  1. Negative Kinetic Energy? (Replies: 13)

  2. Bose-Hubbard Model (Replies: 5)

Loading...