Broken rotational symmetry on the Fermi surface of a high-Tc superconductor

Abstract

Condensed matter physics: Rotational symmetry breaking in unconventional superconductors Observations of broken rotational symmetry in YBa2Cu3O6.58 suggest that it could be a universal feature in unconventional superconductors. The origin of superconductivity in materials that do not conform to conventional Bardeen–Cooper–Schrieffer theory remains an important puzzle for condensed matter physicists; one that could hold the key to designing materials that have no resistance near room temperature. An international team of researchers led by Brad Ramshaw used angle-dependent magnetoresistance measurements to directly reveal a broken rotational symmetry on the Fermi surface of underdoped crystals of the copper oxide-based unconventional superconductor YBa2Cu3O6.58. As this feature has been found in several other classes of unconventional superconductors, the authors suggest that this may be a universal feature, which could play an important role in the unconventional formation of superconducting pairs.