Vortex lattice in Bi2Sr2CaCu2O8+δ well above the first-order phase-transition boundary

Abstract Measurements of non-local in-plane resistance originating from transverse vortex–vortex correlations have been performed on a Bi 2 Sr 2 CaCu 2 O 8+ δ high- T c superconductor in a magnetic field up to 9 T applied along the crystal c -axis. Our results demonstrate that a rigid vortex lattice does exist over a broad portion of the magnetic field–temperature ( H – T ) phase diagram, well above the first-order transition (FOT) boundary H FOT ( T ). The results also provide evidence for the vortex lattice melting and vortex liquid decoupling phase transitions, occurring above the H FOT ( T ).