Titvinidze I, Snoek M, Hofstetter W
Institut für Theoretische Physik, Johann Wolfgang Goethe-Universität, 60438 Frankfurt am Main, Germany.
Phys Rev Lett. 2008 Mar 14;100(10):100401. doi: 10.1103/PhysRevLett.100.100401. Epub 2008 Mar 10.
We study a mixture of strongly interacting bosons and spinless fermions with on-site repulsion in a three-dimensional optical lattice. For this purpose we develop and apply a generalized dynamical mean-field theory, which is exact in infinite dimensions and reliably describes the full range from weak to strong coupling. We restrict ourselves to half filling. For weak Bose-Fermi repulsion a supersolid forms, in which bosonic superfluidity coexists with charge-density wave order. For stronger interspecies repulsion the bosons become localized while the charge-density wave order persists. The system is unstable against phase separation for weak repulsion among the bosons.
我们研究了三维光学晶格中具有在位排斥作用的强相互作用玻色子和无自旋费米子的混合物。为此，我们开发并应用了一种广义动态平均场理论，该理论在无限维中是精确的，并且能够可靠地描述从弱耦合到强耦合的整个范围。我们将研究限制在半填充情况下。对于弱的玻色 - 费米排斥，会形成一种超固体，其中玻色子超流性与电荷密度波序共存。对于更强的种间排斥，玻色子会局域化，而电荷密度波序仍然存在。对于玻色子之间的弱排斥，系统对相分离是不稳定的。
