  We report comprehensive (magneto)transport studies of the two-phase state in
(TMTSF)2ClO4, where superconducting (SC) phase coexists with spin-density wave
insulator (SDW). By tuning the degree of ClO4 anion ordering in controlled
manner we drive SDW state and study the evolution of the SC spatial texture. We
find that as SDW is suppressed, SC regions initially appear inside the SDW
insulator in a form of filaments extended in the interlayer direction and
further merge into the two-dimensional sheets across the most conducting axis
of the crystal. We demonstrate that almost all our results can be explained
within the soliton phase model, though with several assumptions they can also
be interpreted by the creation of non-uniform deformations. We believe that the
anisotropy is intrinsic to SC/SDW coexistence in quasi one-dimensional
superconductors.

Superconductivity;Strongly Correlated Electrons