Domain Evolution in Striped Phases of Cuprate Superconductors

Symmetry breaking and recovery in condensed matter systems are closely related to the exotic physical properties of these materials – superconductivity, magnetism, ferroelectricity, etc. A key signature of broken symmetry is the formation of structural domains, often on the nanometer size scale. Recent and upcoming implementations of coherent X-ray diffraction techniques can enable novel experimental opportunities to directly visualize the symmetry changes in quantum materials through the domain structure.

We have pushed Bragg Coherent Diffractive Imaging (BCDI) into the cryogenic regime where most phase transitions in quantum materials reside. Utilizing coherent photons at 34-ID-C beamline of the Advanced Photon Source, we studied the low-temperature phases of the classical cuprate superconductor La_2-xBa_xCuO₄. These phases break the local four-fold rotational symmetry of its high temperature tetragonal (HTT) structure. Our preliminary data suggests the low-temperature-orthorhombic (LTO) phase is not pinned to local crystal disorder or defects. We will briefly discuss the relation between LTO and the charge order.