Domain walls at the spin density wave endpoint of the organic superconductor (TMTSF)2PF6 under pressure

TL;DR

This study investigates the complex phase coexistence and domain wall structures near the spin density wave endpoint in the organic superconductor (TMTSF)2PF6 under pressure, revealing dimensional crossovers in superconductivity.

Contribution

It provides the first detailed experimental evidence of 1D and 2D metallic domains and their role in the transition to superconductivity near the phase boundary.

Findings

Existence of 1D and 2D metallic domains

Dimensional crossover from filamentary to 2D superconductivity

Possible relation to soliton phase formation

Abstract

We report the first comprehensive investigation of the organic superconductor (TMTSF)2PF6 in the vicinity of the endpoint of the spin density wave - metal phase transition where phase coexistence occurs. At low temperature, the transition of metallic domains towards superconductivity is used to reveal the various textures. In particular, we demonstrate experimentally the existence of 1D and 2D metallic domains with a cross-over from a filamentary superconductivity mostly along the c?-axis to a 2D superconductivity in the b?c-plane perpendicular to the most conducting direction. The formation of these domain walls may be related to the proposal of a soliton phase in the vicinity of the critical pressure of the (TMTSF)2PF6 phase diagram.