Precise texture determination of the spin density wave/superconductivity mixture in the phase separation regime of (TMTSF)2PF6

At low temperature, in a narrow range of pressure, the organic conductor (TMTSF)(2)PF6 exhibits a phase coexistence between two ground states, a spin density wave (SDW) state and a metallic state which presents a superconducting (SC) transition at low temperature. This phase coexistence regime extends from 6.7 kbar up to 9.5 kbar. From resistivity measurements performed along the three crystallographic a-, b'- and c*-axes, we are able to extract an image of the evolution of the texture of (TMTSF)(2)PF6 in its phase coexistence regime at low temperatures: at low SC concentration, SC regions form bubbles mostly extended along the c-axis. Upon increasing the pressure, these bubbles extend to filaments along the c-axis which then stacks to form slabs perpendicular to the c*-axis in agreement with theoretical work on the formation of solitons in an SDW system. (c) 2008 Elsevier B.V. All rights reserved.