Verdene T, Beidenkopf H, Myasoedov Y, Shtrikman H, Rappaport M, Zeldov E, Tamegai T
Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot 76100, Israel.
Phys Rev Lett. 2008 Oct 10;101(15):157003. doi: 10.1103/PhysRevLett.101.157003. Epub 2008 Oct 8.
A low concentration of columnar defects is reported to transform a first-order vortex lattice melting line in Bi2Sr2CaCu2O8 crystals into alternating segments of first- and second-order transitions separated by two critical points. As the density of columnar defects is increased, the critical points shift apart and the range of the intermediate second-order transition expands. The measurement of equilibrium magnetization and the mapping of the melting line down to 27 K was made possible by employment of the shaking technique.
