Vortexlike excitations in a nonsuperconducting single-layer compound Bi2+xSr2-xCuO6+delta single crystal in high magnetic fields

[摘要] The in-plane rho(ab)(H,T) and the out-of-plane rho(c)(H,T) magnetotransport in magnetic fields up to 28 T has been investigated in high-quality nonsuperconducting (down to 20 mK) La-free Bi2+xSr2-xCuO6+delta single crystal. By measuring the angular dependence of the in-plane and out-of-plane magnetoresistivities at temperatures from 1 K down to 30 mK, we present evidence for the presence of vortexlike excitations in a nonsuperconducting cuprate in the insulating state. Such excitations have previously been observed by the detection of a Nernst signal in superconducting cuprates at T>T-c in magnetic fields.

[发布日期] 2005-12-01

[关键词] NEGATIVE MAGNETORESISTANCE;DEPENDENCE;TRANSITIONS