01646nas a2200157 4500008004100000245004100041210004100082260001500123490000700138520122200145100002301367700002101390700002001411700002001431856003701451 2010 eng d00aHeavy fermions in an optical lattice0 aHeavy fermions in an optical lattice c2010/11/220 v823 a We employ a mean-field theory to study ground-state properties and transport
of a two-dimensional gas of ultracold alklaline-earth metal atoms governed by
the Kondo Lattice Hamiltonian plus a parabolic confining potential. In a
homogenous system this mean-field theory is believed to give a qualitatively
correct description of heavy fermion metals and Kondo insulators: it reproduces
the Kondo-like scaling of the quasiparticle mass in the former, and the same
scaling of the excitation gap in the latter. In order to understand
ground-state properties in a trap we extend this mean-field theory via
local-density approximation. We find that the Kondo insulator gap manifests as
a shell structure in the trapped density profile. In addition, a strong
signature of the large Fermi surface expected for heavy fermion systems
survives the confinement, and could be probed in time-of-flight experiments.
From a full self-consistent diagonalization of the mean-field theory we are
able to study dynamics in the trap. We find that the mass enhancement of
quasiparticle excitations in the heavy Fermi liquid phase manifests as slowing
of the dipole oscillations that result from a sudden displacement of the trap
center.
1 aFoss-Feig, Michael1 aHermele, Michael1 aGurarie, Victor1 aRey, Ana, Maria uhttp://arxiv.org/abs/1007.5083v100925nas a2200145 4500008004100000245006200041210006200103260001300165490000700178520049300185100002300678700002100701700002000722856003700742 2010 eng d00aProbing the Kondo Lattice Model with Alkaline Earth Atoms0 aProbing the Kondo Lattice Model with Alkaline Earth Atoms c2010/5/70 v813 a We study transport properties of alkaline-earth atoms governed by the Kondo
Lattice Hamiltonian plus a harmonic confining potential, and suggest simple
dynamical probes of several different regimes of the phase diagram that can be
implemented with current experimental techniques. In particular, we show how
Kondo physics at strong coupling, low density, and in the heavy fermion phase
is manifest in the dipole oscillations of the conduction band upon displacement
of the trap center.
1 aFoss-Feig, Michael1 aHermele, Michael1 aRey, Ana, Maria uhttp://arxiv.org/abs/0912.4762v1