The collective dynamics of a dipolar fermionic quantum gas confined in a one-dimensional double-well superlattice is explored. The fermionic gas resides in a paramagnetic-like ground state in the weak interaction regime, upon which a new type of collective dynamics is found when applying a local perturbation. This dynamics is composed of the local tunneling of fermions in separate supercells, and is a pure quantum effect, with no classical counterpart. Due to the presence of the dipolar interactions the local tunneling transports through the entire superlattice, giving rise to a collective dynamics. A well-defined momentum-energy dispersion relation is identified in the ab-initio simulations demonstrating the phonon-like behavior. The phonon-like characteristic is also confirmed by an analytical description of the dynamics within a semiclassical picture.The collective dynamics of a dipolar fermionic quantum gas confined in a one-dimensional double-well superlattice is explored. The fermionic gas resides in a paramagnetic-like ground state in the weak interaction regime, upon which a new type of collective dynamics is found when applying a local perturbation. This dynamics is composed of the local tunneling of fermions in separate supercells, and is a pure quantum effect, with no classical counterpart. Due to the presence of the dipolar interactions the local tunneling transports through the entire superlattice, giving rise to a collective dynamics. A well-defined momentum-energy dispersion relation is identified in the ab-initio simulations demonstrating the phonon-like behavior. The phonon-like characteristic is also confirmed by an analytical description of the dynamics within a semiclassical picture.

Jun 27, 20160 citations

Collective excitations of a dipolar atomic condensate

Su Yi, Li You

APSMay 1, 20010 citations

Collective modes of monolayer, bilayer, and multilayer fermionic dipolar liquid

Qiuzi Li, E. H. Hwang, S. Das Sarma

Motivated by recent experimental advances in creating polar molecular gases in the laboratory, we theoretically investigate the many-body effects of two-dimensional (2D) dipolar systems with the anisotropic and $1/{r}^{3}$ dipole-dipole interactions. We calculate collective modes of 2D dipolar systems and also consider spatially separated bilayer and multilayer superlattice dipolar systems. We obtain the characteristic features of collective modes in quantum dipolar gases. We quantitatively compare the modes of these dipolar systems with the modes of the extensively studied usual two-dimensional electron systems, where the interparticle interaction is Coulombic.Motivated by recent experimental advances in creating polar molecular gases in the laboratory, we theoretically investigate the many-body effects of two-dimensional (2D) dipolar systems with the anisotropic and $1/{r}^{3}$ dipole-dipole interactions. We calculate collective modes of 2D dipolar systems and also consider spatially separated bilayer and multilayer superlattice dipolar systems. We obtain the characteristic features of collective modes in quantum dipolar gases. We quantitatively compare the modes of these dipolar systems with the modes of the extensively studied usual two-dimensional electron systems, where the interparticle interaction is Coulombic.

arXiv:1009.4204Physical Review BDec 16, 201025 citations

1/{r}^{3}

dipole-dipole interactions. We calculate collective modes of 2D dipolar systems and also consider spatially separated bilayer and multilayer superlattice dipolar systems. We obtain the characteristic features of collective modes in quantum dipolar gases. We quantitatively compare the modes of these dipolar systems with the modes of the extensively studied usual two-dimensional electron systems, where the interparticle interaction is Coulombic.