Tunneling Qubit Operation on a Protected Josephson Junction Array

We discuss a protected quantum computation process based on a hexagon Josephson junction array. Qubits are encoded in the punctured array, which is topologically protected. The degeneracy is related to the number of holes. The topological degeneracy is lightly shifted by tuning the flux through specific hexagons. We also show how to perform single qubit operation and basic quantum gate operations in this system.Comment: 8 pages, 4 figures. The published version in Phys. Rev., A81(2010)01232

Poly[μ2-aqua-[μ2-1,1′-(butane-1,4-di­yl)diimidazole]bis­(μ4-naphthalene-1,4-dicarboxyl­ato)dimanganese(II)]

In the title compound, [Mn2(C12H6O4)2(C10H14N4)(H2O)]n or [Mn2(1,4-ndc)2(L)(H2O)]n, where 1,4-ndc is naphthalene-1,4-dicarboxyl­ate and L is 1,1′-(butane-1,4-di­yl)diimidazole, the coordination polyhedron around each MnII atom is distorted octa­hedral. The water mol­ecule and the L ligand are situated across a twofold rotation axis. The MnII atoms are bridged by 1,4-ndc and L ligands, forming a three-dimensional network. O—H⋯O hydrogen bonds are observed within the network

Poly[μ-aqua-[μ-1,1′-(butane-1,4-di­yl)diimidazole]bis­(μ4-naphthalene-1,4-dicarboxyl­ato)dicadmium(II)]

In the title compound, [Cd2(C12H6O4)2(C10H14N4)(H2O)]n, the coordination polyhedron around each CdII ion is a distorted CdNO5 octa­hedron. The water O atom has site symmetry 2 and the complete 1,1′-(butane-1,4-di­yl)diimidazole (L) ligand is generated by inversion. The naphthalene-1,4-dicarboxyl­ate and L ligands bridge the metal centres, forming a three-dimensional framework, which is consolidated by O—H⋯O hydrogen bonds

Poly[tris­(μ-benzene-1,4-dicarboxylato)bis­(dipyrido[3,2-a:2′,3′-c]phenazine)trimanganese(II)]

In the title compound, [Mn3(C8H4O4)3(C14H8N4)2]n, one Mn atom is located on an inversion centre and is six-coordinated by four carboxyl­ate O atoms from different benzene-1,4-dicarboxyl­ate (1,4-bdc) ligands and two phenanthrene N atoms from a dipyrido[3,2-a:2′,3′-c]phenazine ligand. The other Mn atom is also six-coordinate, binding to six carboxyl­ate O atoms from different 1,4-bdc ligands. The dicarboxyl­ate groups chelate and bridge the two Mn atoms and a symmetry-related Mn atom to form a trimanganese unit. Bridging of the trinuclear MnII clusters leads to a two-dimensional structure