Observation of a magnetic state in the organic superconductor (TMTSF) 2ClO4 : influence of the cooling rate

T. Takahashi , D. Jérome , K. Bechgaard

A magnetic state is observed below ∼ 3.5 K in the organic superconductor (TMTSF)2ClO4 just above the superconducting transition (Tc ∼ 1 K). This state is obtained by fast cooling with a rate of ∼ 25 K/min. and evidenced by 77Se and 1H-NMR intensity and relaxation measurements. The onset temperature is nearly field-independent between 10 and 65 kOe. In the same sample, slow cooling suppresses the magnetism to at least below 1.3 K. The heat cycle effects are fully reproducible. The results imply that fast cooling freezes in lattice disorder which depresses superconductivity and therefore leave room for the competing magnetic phase. A small hydrostatic pressure also depresses the magnetism

Mots clés: cooling; magnetic transition temperature; NMR line breadth; nuclear spin lattice relaxation; organic compounds; proton magnetic resonance; type II superconductors; magnetic state; organic superconductor; TMTSF sub 2 ClO sub 4; cooling rate; superconducting transition; sup 77 Se; sup 1 H; NMR; relaxation; onset temperature; heat cycle effects; lattice disorder; hydrostatic pressure

Domaines: Articles anciens

T. Takahashi, D. Jérome, K. Bechgaard. Observation of a magnetic state in the organic superconductor (TMTSF) 2ClO4 : influence of the cooling rate. Journal de Physique Lettres, 1982, 43 (15), pp.565-573. ⟨10.1051/jphyslet:019820043015056500⟩. ⟨jpa-00232093⟩