PECULIARITIES OF VORTEX STATE OF BI-2212 SINGLE-CRYSTALS

A phase diagram of the vortex state of Bi-2212 single crystals in a ma gnetic field parallel to the (c) over cap-axis proposed under the assu mption on the two-stage destruction of long-range vortex correlation i n such crystals matches with the experimental results obtained by usin g different methods.(1-7) The intersection of the dimensional crossove r line B-cr(T) with the line corresponding to violation of long-range vortex correlations in the (<(ab)over cap>)-plane makes it possible to explain the discontinuity at the critical point of the vortex lattice melting curve T-m(B). Possibilities of experimental investigation of low-temperature condensed state for B>B-cr and the temperature depende nce B-cr(T) are considered. (C) 1998 American Institute of Physics.