Spin rotational symmetry breaking by orbital current patterns in two-leg ladders.
arXiv:1003.4415 · doi:10.1103/PhysRevB.81.165402
Abstract
We investigate the physical consequences of orbital current patterns (OCP) in doped two-leg Cu-O Hubbard ladders. The internal symmetry of the pattern, in the case of the ladder structure, differs slightly from that suggested so far for cuprates. We focus on this OCP and look for measurable signatures of its existence. We compute the magnetic field produced by the OCP at each lattice site, and estimate its value in view of a possible experimental detection. Using a renormalization group (RG) analysis, we determine the changes that are caused by the SU(2) spin-rotational symmetry breaking which occurs when the OCP is present in the ground state phase diagram. The most signifcant one is an in-plane SDW gap opening in an otherwise critical phase, at intermediate dopings. We estimate the value of this gap, give an analytic expression for the correlation functions and examine some of the magnetic properties of this new phase which can be revealed in measurements. We compute the conductance in the presence of a single impurity, using an RG analysis. A discussion of the various sources of SU(2) symmetry breaking underscores the specificity of the OCP induced effects.
12 pages, 3 figures, submitted to PRB
References in corpus (10)
- Magnetic order in the pseudogap phase of high- superconductors
- Polar Kerr Effect Measurements of YBa2Cu3O6+x: Evidence for Broken Symmetry Near the Pseudogap Temperature
- Electronic Orbital Currents and Polarization in Mott Insulators
- Polar Kerr Effect as Probe for Time-Reversal Symmetry Breaking in Unconventional Superconductors
- Orbital currents in extended Hubbard models of high-T cuprates
- Broken time-reversal symmetry in strongly correlated ladder structures
- Detection of the Unusual Magnetic Orders in the Pseudogap Region of a High-Temperature Superconducting YBa2Cu3O6.6 Crystal by Muon-Spin Relaxation
- Numerical analysis of three-band models for CuO planes as candidates for a spontaneous T violating orbital current phase
- Coherence and pairing in a doped Mott insulator: Application to the cuprates
- Influence of non-magnetic impurities on hole doped two-leg Cu-O Hubbard ladders