1202.4782 (Michael Schecter et al.)

Forming doublons by a quantum quench    [PDF]

Michael Schecter, Alex Kamenev

Repulsive interactions between particles on a lattice may lead to bound
states, so called doublons. Such states may be created by dynamically tuning
the interaction strength, e.g. using a Feshbach resonance, from attraction to
repulsion. We study the doublon production efficiency as a function of the
tuning rate at which the on-site interaction is varied. An expectation based on
the Landau- Zener law suggests that exponentially few doublons are created in
the adiabatic limit. Contrary to such an expectation, we found that the number
of produced doublons scales as a power law of the tuning rate with the exponent
dependent on the dimensionality of the lattice. The physical reason for this
anomaly is the effective decoupling of doublons from the two-particle continuum
for center of mass momenta close to the corners of the Brillouin zone. The
study of doublon production may be a sensitive tool to extract detailed
information about the band structure.

View original: http://arxiv.org/abs/1202.4782