Effects of vortex and antivortex excitations in underdoped Bi2Sr2Ca2Cu3O10+δ bulk single crystals

The observance of vortex and antivortex effects in bulk crystals can prove the existence of phase-disordered superconductivity in the bulk. To gain insights into the mechanisms that govern superconducting transition in copper oxide high-transition temperature (Tc) T c ) superconductors, this study investigated the transport properties of underdoped Bi2Sr2Ca2Cu3O10+delta(Bi-2223) 2 Sr 2 Ca 2 Cu 3 O 10 +delta (Bi-2223) bulk single crystals. The I-V V characteristics results and the typical tailing behavior owing to the temperature dependence of in-plane resistivity (rho ab) rho ab ) were consistent with the Kosterlitz-Thouless (KT) transition characteristics. Thus, with increasing temperature, copper oxide high-Tc T c superconductors transitioned to their normal state owing to destruction of their phase correlations, although a finite Cooper pair density was prevalent at T c . Further, magnetization measurements were performed to determine the temperature dependence of the irreversible magnetic field B irr . Consequently, the mechanism governing the KT transition-like superconducting transition in this bulk system was elucidated. These results support the extreme strong-coupling models for high-Tc T c superconductivity in cuprates.