The Coulomb Branch of Yang-Mills Theory from the Schroedinger Representation

The Coulomb branch of the potential between two static colored sources is calculated for the Yang-Mills theory using the electric Schroedinger representation.Comment: 4 pages, no figures, REVTEX, as in Phys. Lett.

Quantum computation with abelian anyons on the honeycomb lattice

We consider a two-dimensional spin system that exhibits abelian anyonic excitations. Manipulations of these excitations enable the construction of a quantum computational model. While the one-qubit gates are performed dynamically the model offers the advantage of having a two-qubit gate that is of topological nature. The transport and braiding of anyons on the lattice can be performed adiabatically enjoying the robust characteristics of geometrical evolutions. The same control procedures can be used when dealing with non-abelian anyons. A possible implementation of the manipulations with optical lattices is developed.Comment: 4 pages, 3 figures, REVTEX, improved presentation and implementatio

Detecting Majorana bound states

We propose a set of interferometric methods on how to detect Majorana bound states induced by a topological insulator. The existence of these states can be easily determined by the conductance oscillations as function of magnetic flux and/or electric voltage. We study the system in the presence and absence of Majorana bound states and observe strikingly different behaviors. Importantly, we show that the presence of coupled Majorana bound states can induce a persistent current in absence of any external magnetic field.Comment: 7 pages, 6 figures, 1 table, revised and expanded, accepted for publication in Phys. Rev.

The Schrodinger representation for ϕ(^4) theory and the O(N) σ-model

In this work we apply the field theoretical Schrodinger representation to the massive ϕ(^4) theory and the O(N) σ model in 1 + 1 dimensions. The Schrodinger equation for the ϕ(^4) theory is reviewed and then solved classically and semiclassically, to obtain the vacuum functional as an expansion of local functionals. These results are compared with equivalent ones derived from the path integral formulation to prove their agreement with the conventional field theoretical methods. For the O(N) a model we construct the functional Laplacian, which is the principal ingredient of the corresponding Schrodinger equation. This result is used to construct the generalised Virasoro operators for this model and study their algebra

Effective three-body interactions in triangular optical lattices

We demonstrate that a triangular optical lattice of two atomic species, bosonic or fermionic, can be employed to generate a variety of novel spin-1/2 Hamiltonians. These include effective three-spin interactions resulting from the possibility of atoms tunneling along two different paths. Such interactions can be employed to simulate particular one or two dimensional physical systems with ground states that possess a rich structure and undergo a variety of quantum phase transitions. In addition, tunneling can be activated by employing Raman transitions, thus creating an effective Hamiltonian that does not preserve the number of atoms of each species. In the presence of external electromagnetic fields, resulting in complex tunneling couplings, we obtain effective Hamiltonians that break chiral symmetry. The ground states of these Hamiltonians can be used for the physical implementation of geometrical or topological objects.Comment: 10 pages, 5 figures, REVTEX. Experimental implementation elaborated, brief study of ground states give