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We report femtosecond resonant soft X-ray diffraction measurements of the dynamics of the charge order and of the crystal lattice in non-superconducting, stripe-ordered La1.875Ba0.125CuO4. Excitation of the in-plane Cu-O stretching phonon with a mid-infrared pulse has been previously shown to induce a transient superconducting state in the closely related compound La1.675Eu0.2Sr0.125CuO4. In La1.875Ba0.125CuO4, we find that the charge stripe order melts promptly on a sub-picosecond time scale. Surprisingly, the low temperature tetragonal distortion is only weakly reduced, reacting on significantly longer time scales that do not correlate with light-induced superconductivity. This experiment suggests that charge modulations alone, and not the LTT distortion, prevent superconductivity in equilibrium.
Recent theories of charge density wave (CDW) order in high temperature superconductors have predicted a primarily d CDW orbital symmetry. Here, we report on the orbital symmetry of CDW order in the canonical cuprate superconductors La1.875Ba0.125CuO4
Vortex matter phase transitions in the high-temperature superconductor Bi2Sr2CaCu2O8 were studied using local magnetization measurements combined with a vortex shaking technique. The measurements revealed thermodynamic evidence of a first-order trans
The dynamic phase diagram of vortex lattices driven in disorder is calculated in two and three dimensions. A modified Lindemann criterion for the fluctuations of the distance of neighboring vortices is used, which unifies previous analytic approaches
We thoroughly examine the ground state of the triangular lattice of Pb on Si(111) using scanning tunneling microscopy. We detect charge-order, accompanied by a subtle structural reconstruction. Applying the extended variational cluster approach we ma
In a multiorbital model of the cuprate high-temperature superconductors soft antiferromagnetic (AF) modes are assumed to reconstruct the Fermi surface to form nodal pockets. The subsequent charge ordering transition leads to a phase with a spatially