Neutron scattering study of spin ordering and stripe pinning in superconducting La 1.93 Sr 0.07 CuO 4

摘要: The relationships among charge order, spin fluctuations, and superconductivity in underdoped cuprates remain controversial. We use neutron scattering techniques to study these phenomena ${\mathrm{La}}_{1.93}{\mathrm{Sr}}_{0.07}{\mathrm{CuO}}_{4}$, a superconductor with transition temperature of ${T}_{c}=20$ K. At $T\ensuremath{\ll}{T}_{c}$ we find incommensurate fluctuations quasielastic energy spectrum no sign gap within the range from 0.2 15 meV. A weak elastic magnetic component grows below $\ensuremath{\sim}10$ K, consistent results local probes. Regarding atomic lattice, have discovered unexpectedly strong ${\mathrm{CuO}}_{6}$ octahedra about Cu-O bonds, which are associated inequivalent O sites ${\mathrm{CuO}}_{2}$ planes. Furthermore, observed $(3\overline{3}0)$ superlattice peak that implies reduced lattice symmetry. presence rationalizes various pieces evidence for stripe order ${\mathrm{La}}_{2\ensuremath{-}x}{\mathrm{Sr}}_{x}{\mathrm{CuO}}_{4}$. coexistence quasistatic spin-stripe suggests intertwined orders; however, rotation orientation away bonds might be connected finite at nodal points superconducting function.