Doping dependence of upper critical field and hall resistivity in LaFeAsO1-xFx (x=0, 0.025, 0.5, 0.07, 0.11 and 0.14)

Journal Article · Tue Jan 01 00:00:00 EST 2008 · Physical Review Letters

OSTI ID:960692

Kohima, Yoshimitsu ^[1]; Baily, S A ^[1]; Civale, L ^[1]; Riggs, S C ^[1]; Balakirev, F F ^[1]; Jaime, M ^[1]; Kamihara, Y ^[2]; Atake, T ^[2]; Hirano, M ^[3]; Hosono, H ^[3]

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1. Los Alamos National Laboratory
2. JAPAN
3. TOKYO INSTIT

The electrical resistivity ({rho}{sub xx}) and Hall resistivity ({rho}{sub xy}) have been measured over wide composition range using 60 T pulsed magnets. While the superconducting phase diagram (T{sub c}, x) displays the classic dome-shaped structure, we find that the upper critical field (H{sub c2}) increases monotonically with decreasing fluorine concentration (x), with the largest H{sub c2} {>=} 75 T for x = 0.05. {rho}{sub xx} and {rho}{sub xy} data provide evidence for the multiband electronic structure for all x {<=} 0.14 in LaFeAsO{sub 1-x}F{sub x}, and demonstrate the quantum phase transition near x {approx} 0.05. Both the multiband structure and quantum phase transition play crucial roles in the large H{sub c2}.

• Research Organization: Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC52-06NA25396
• OSTI ID: 960692
• Report Number(s): LA-UR-08-05972; LA-UR-08-5972; PRLTAO; TRN: US201008%%625
• Journal Information: Physical Review Letters, Journal Name: Physical Review Letters; ISSN 0031-9007
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ARSENIC COMPOUNDS
CRITICAL FIELD
CRYSTAL DOPING
ELECTRIC CONDUCTIVITY
ELECTRONIC STRUCTURE
FLUORINE ADDITIONS
HIGH-TC SUPERCONDUCTORS
IRON COMPOUNDS
LANTHANUM COMPOUNDS
MAGNETS
PHASE DIAGRAMS
SUPERCONDUCTIVITY