title: Melting of "porous" vortex matter.
abstract: Bitter decoration and magneto-optical studies reveal that in heavy-ion irradiated superconductors, a "porous" vortex matter is formed when vortices outnumber columnar defects. In this state ordered vortex crystallites are embedded in the "pores" of a rigid matrix of vortices pinned on columnar defects. The crystallites melt through a first-order transition while the matrix remains solid. The melting temperature increases with density of columnar defects and eventually turns into a continuous transition. At high temperatures a sharp kink in the melting line is found, signaling an abrupt change from crystallite melting to melting of the rigid matrix.
authors.affiliation: Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot 76100, Israel.
authors.forename: S S
authors.initials: SS
authors.lastname: Banerjee
authors.forename: A
authors.initials: A
authors.lastname: Soibel
authors.forename: Y
authors.initials: Y
authors.lastname: Myasoedov
authors.forename: M
authors.initials: M
authors.lastname: Rappaport
authors.forename: E
authors.initials: E
authors.lastname: Zeldov
authors.forename: M
authors.initials: M
authors.lastname: Menghini
authors.forename: Y
authors.initials: Y
authors.lastname: Fasano
authors.forename: F
authors.initials: F
authors.lastname: de la Cruz
authors.forename: C J
authors.initials: CJ
authors.lastname: van der Beek
authors.forename: M
authors.initials: M
authors.lastname: Konczykowski
authors.forename: T
authors.initials: T
authors.lastname: Tamegai