Quantum critical point and superconducting dome in the pressure phase diagram of o-TaS3

M. Monteverde , Jose Lorenzana (1) , Pierre Monceau (2) , Manuel Nunez-Regueiro (2)

1 Dipartimento di Fisica [Roma La Sapienza]
2 NEEL - MagSup - Magnétisme et Supraconductivité

We measure the electrical resistance of o-TaS3 between 1 and 300 K under pressures up to 20 GPa. We observe a gradual decrease of the charge density wave transition temperature T-CDW with increasing pressure P following a mean field quantum fluctuation power law T-CDW = 215 K[(P-C - P)/P-C](gamma) with a quantum critical point at a pressure P-C = 11.5 GPa and gamma approximate to 0.5. Around the quantum critical point (QCP) we observe a superconducting dome with a maximum superconducting transition temperature T-c = 3.1 K. Such dome is similar to superconducting domes around other types of order suggesting that the QCP is directly responsible for the enhancement of superconductivity through a universal mechanism still not well understood.

Domaines: Electrons fortement corrélés [cond-mat.str-el]

M. Monteverde, Jose Lorenzana, Pierre Monceau, Manuel Nunez-Regueiro. Quantum critical point and superconducting dome in the pressure phase diagram of o-TaS3. Physical Review B: Condensed Matter and Materials Physics (1998-2015), 2013, 88 (18), pp.180504(R). ⟨10.1103/PhysRevB.88.180504⟩. ⟨hal-00966284⟩