Probing the connections between superconductivity, stripe order, and structure in La ${}_{1.905}$ Ba ${}_{0.095}$ Cu ${}_{1-y}$ Zn ${}_y$ O ${}_4$

Journal Article · Sun Apr 01 00:00:00 EDT 2012 · Physical Review. B, Condensed Matter and Materials Physics

DOI:https://doi.org/10.1103/PhysRevB.85.134512· OSTI ID:1059737

Wen, Jinsheng; Xu, Zhijun; Xu, Guangyong; Jie, Qing; Hücker, M.; Zheludev, A.; Tian, Wei; Winn, B. L.; Zarestky, J. L.; Singh, D. K.; Hong, Tao; Li, Qiang; Gu, Genda; Tranquada, J. M.

The superconducting system La_2-xBa_xCuO₄ is known to show a minimum in the transition temperature T_c at x=1/8 where maximal stripe order is pinned by the anisotropy within the CuO₂ planes that occurs in the low-temperature-tetragonal (LTT) crystal structure. For x=0.095, where Tc reaches its maximum value of 32 K, there is a roughly coincident structural transition to a phase that is very close to LTT. Here, we present a neutron scattering study of the structural transition, and demonstrate how features of it correlate with anomalies in the magnetic susceptibility, electrical resistivity, thermal conductivity, and thermoelectric power. We also present measurements on a crystal with 1% Zn substituted for Cu, which reduces T_c to 17 K, enhances the spin stripe order, but has much less effect on the structural transition. We make the case that the structural transition correlates with a reduction of the Josephson coupling between the CuO₂ layers, which interrupts the growth of the superconducting order. We also discuss evidence for two-dimensional superconducting fluctuations in the normal state, analyze the effective magnetic moment per Zn impurity, and consider the significance of the anomalous thermopower often reported in the stripe-ordered phase.

• Research Organization: Brookhaven National Lab. (BNL), Upton, NY (United States)
• Sponsoring Organization: USDOE SC OFFICE OF SCIENCE (SC)
• DOE Contract Number: DE-AC02-98CH10886
• OSTI ID: 1059737
• Report Number(s): BNL-96622-2012-JA; PRBMDO; R&D Project: PO-010; KC0202010
• Journal Information: Physical Review. B, Condensed Matter and Materials Physics, Vol. 85, Issue 13; ISSN 1098-0121
• Publisher: American Physical Society (APS)
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY