Electronic phase diagram of the iron-based high-Tc superconductor Ba(Fe1 xCox)2As2 under hydrostatic pressure (0 is less than or equal to x is less than or equal to 0.099)

Journal Article · Thu Jan 01 04:00:00 EST 2009 · Physical Review B

DOI:https://doi.org/10.1103/PhysRevB.79.214520· OSTI ID:962167

Ahilan, K. ^[1]; Ning, F. L. ^[1]; Imai, T. ^[1]; Safa-Sefat, Athena ^[2]; McGuire, Michael A ^[2]; Sales, Brian C ^[2]; Mandrus, David ^[2]

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1. McMaster University
2. ORNL

We report comprehensive resistivity measurements of single-crystalline samples of the Ba(Fe{sub 1-x}Co{sub x}){sub 2}As{sub 2} high-T{sub c} superconductor under hydrostatic pressure up to 2.75 GPa and over a broad concentration range, 0 {le} x {le} 0.099. We show that application of pressure progressively suppresses the spin-density wave (SDW) transition temperature, T{sub SDW}, in the underdoped regime (x {approx}< 0.051). There is no sign of pressure-induced superconductivity in the undoped BaFe{sub 2}As{sub 2} down to 1.8 K but applied pressure dramatically enhances T{sub c} in the underdoped regime 0.02 {approx}< x {approx}< 0.051. The effect of pressure on T{sub c} is very small in the optimally and overdoped regimes 0.082 {approx}< x {approx}< 0.099. As a consequence, the dome of the superconducting phase extends to x {approx}< 0.02 under pressure. We discuss the implications of our findings in the context of a possible quantum phase transition between the SDW and superconducting phases.

• Research Organization: Oak Ridge National Laboratory (ORNL)
• Sponsoring Organization: SC USDOE - Office of Science (SC)
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 962167
• Journal Information: Physical Review B, Journal Name: Physical Review B Journal Issue: 21 Vol. 79; ISSN 1098-0121
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ARSENIC ALLOYS
BARIUM ALLOYS
COBALT ALLOYS
DOPED MATERIALS
ELECTRIC CONDUCTIVITY
HIGH-TC SUPERCONDUCTORS
HYDROSTATICS
IRON ALLOYS
PHASE DIAGRAMS
PHASE TRANSFORMATIONS
PRESSURE DEPENDENCE
TRANSITION TEMPERATURE