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Colloquium: Nonequilibrium dynamics of closed interacting quantum systems
This Colloquium gives an overview of recent theoretical and experimental progress in the area of nonequilibrium dynamics of isolated quantum systems. There is particularly a focus on quantum
Mott-insulator–to–superfluid transition in the Bose-Hubbard model: A strong-coupling approach
We present a strong-coupling expansion of the Bose-Hubbard model which describes both the superfluid and the Mott phases of ultracold bosonic atoms in an optical lattice. By performing two successive
Mott insulators in strong electric fields
Recent experiments on ultracold atomic gases in an optical lattice potential have produced a Mott insulating state of ${}^{87}\mathrm{Rb}$ atoms. This state is stable to a small applied potential
Fractional ac Josephson effect in p- and d-wave superconductors
For certain orientations of Josephson junctions between two px-wave or two d-wave superconductors, the subgap Andreev bound states produce a $4\pi$-periodic relation between the Josephson current I
Competing density-wave orders in a one-dimensional hard-boson model
We describe the zero-temperature phase diagram of a model of bosons, occupying sites of a linear chain, which obey a hard-exclusion constraint: any two nearest-neighbor sites may have at most one
Non-perturbative renormalization group approach to zero-temperature Bose systems
We use a non-perturbative renormalization group technique to study interacting bosons at zero temperature. Our approach reveals the instability of the Bogoliubov fixed point when d≤3 and yields the
Quench dynamics across quantum critical points
We study the quantum dynamics of a number of model systems as their coupling constants are changed rapidly across a quantum critical point. The primary motivation is provided by the recent
Hard-core bosons on the kagome lattice: valence-bond solids and their quantum melting.
Using large scale quantum Monte Carlo simulations and dual vortex theory, the ground state phase diagram of hard-core bosons on the kagome lattice with nearest-neighbor repulsion is analyzed, providing evidence for a weakly first-order phase transition at the quantum melting point between these solid phases and the superfluid.
Midgap edge states and pairing symmetry of quasi-one-dimensional organic superconductors
The singlet s-, d- and triplet p-wave pairing symmetries in quasi-one-dimensional organic superconductors can be experimentally discriminated by probing the Andreev bound states at the sample edges.