Now showing items 1-9 of 9

• #### Antiferromagnetism in Metals: From the Cuprate Superconductors to the Heavy Fermion Materials ﻿

(IOP Publishing, 2012)
The critical theory of the onset of antiferromagnetism in metals, with concomitant Fermi surface reconstruction, has recently been shown to be strongly coupled in two spatial dimensions. The onset of unconventional ...
• #### Breakdown of Fermi Liquid Behavior at the (π,π)=2k$_F$ Spin-Density Wave Quantum-Critical Point: the Case of Electron-Doped Cuprates ﻿

(American Physical Society, 2012)
Many correlated materials display a quantum-critical point between a paramagnetic and a spin-density wave (SDW) state. The SDW wave vector connects points, so-called hot spots, on opposite sides of the Fermi surface. The ...
• #### Fermi Surface Reconstruction in Hole-Doped t-J Models without Long-Range Antiferromagnetic Order ﻿

(American Physical Society, 2012)
We calculate the Fermi surface of electrons in hole-doped, extended t-J models on a square lattice in a regime where no long-range antiferromagnetic order is present, and no symmetries are broken. Using the “spinon-dopon” ...
• #### Mobile impurity near the superfluid–Mott-insulator quantum critical point in two dimensions ﻿

(American Physical Society, 2013)
We consider bosonic atoms in an optical lattice at integer filling, tuned to the superfluid-Mott insulator critical point, and coupled to a single, mobile impurity atom of a di↵erent species. This setup is inspired by ...
• #### Optical Conductivity of Visons in Z_{2} Spin Liquids Close to a Valence Bond Solid Transition on the Kagome Lattice ﻿

(American Physical Society (APS), 2013)
We consider Z2 spin liquids on the kagome lattice on the verge of a valence bond solid (VBS) transition, where vortex excitations carrying Z2 magnetic flux—so-called visons—condense. We show that these vison excitations ...
• #### Quantum quenches in the anisotropic spin-\frac{1}{2} Heisenberg chain: different approaches to many-body dynamics far from equilibrium ﻿

(IOP Publishing, 2010)
Recent experimental achievements in controlling ultracold gases in optical lattices open a new perspective on quantum many-body physics. In these experimental setups it is possible to study coherent time evolution of ...
• #### Relaxation of Antiferromagnetic Order in Spin-1/2 Chains Following a Quantum Quench ﻿

(American Physical Society, 2009)
We study the unitary time evolution of antiferromagnetic order in anisotropic Heisenberg chains that are initially prepared in a pure quantum state far from equilibrium. Our analysis indicates that the antiferromagnetic ...
• #### Topological excitations and the dynamic structure factor of spin liquids on the kagome lattice ﻿

(Nature Publishing Group, 2014)
Recent neutron scattering experiments on the spin-1/2 kagome lattice antiferromagnet ZnCu$_3$(OH)$_6$C$_{12}$ (Herbertsmithite) provide the first evidence of fractionalized excitations in a quantum spin liquid state ...
• #### Vison States and Confinement Transitions of $Z_2$ Spin Liquids on the Kagome Lattice ﻿

(American Physical Society, 2011)
We present a projective symmetry group (PSG) analysis of the spinless excitations of $Z_2$ spin liquids on the kagome lattice. In the simplest case, vortices carrying $Z_2$ magnetic flux (“visons”) are shown to transform ...