Fe-based superconductors

R. Klingeler, N. Leps, I. Hellmann, A. Popa, U. Stockert, C. Hess, V. Kataev, H.-J. Grafe, F. Hammerath, G. Lang, S. Wurmehl, G. Behr, L. Harnagea, S. Singh, B. Buechner. Local antiferromagnetic correlations in the iron pnictide superconductors LaFeAsO1-xFx and Ca(Fe1-xCox)2As2 as seen via normal-state susceptibility, Physical Review B 81 (2010) Nr. 2, S. 24506/1-5 URL

R. Klingeler, L. Wang, U. Koehler, G. Behr, C. Hess, B. Buechner. Thermal expansion of RFeAsO (R=La,Ce,Pr,Sm,Gd), Journal of Physics: Conference Series 200 (2010), S. 12088/1-4 URL

N.Y. Panarina, Y.I. Talanov, T.S. Shaposhnikova, N.R. Beysengulov, E.L. Vavilova, V.E. Kataev, G. Behr, A. Kondrat, C. Hess, N. Leps, R. Klingeler, B. Buechner.Microwave absorption study of polycrystalline SmO1-xFxFeAs, Journal of Physics: Conference Series 200 (2010), S. 12154/1-4 URL

A. Alfonsov, F. Muranyi, V. Kataev, N. Leps, R. Klingeler, A. Kondrat, C. Hess, J. Werner, G. Behr, B. Buechner. High field ESR spectroscopy on GdO1-xFxFeAs, Journal of Low Temperature Physics 159 (2010) Nr. 1-2, S. 172-175 URL

D.S. Inosov, J.S. White, D.V. Evtushinsky, I.V. Morozov, A. Cameron, U. Stockert, V.B. Zabolotnyy, T.K. Kim, A.A. Kordyuk, S.V. Borisenko, E.M. Forgan, R. Klingeler, J.T. Park, S. Wurmehl, A.N. Vasiliev, G. Behr, C.D. Dewhurst, V. Hinkov.Weak superconducting pairing and a single isotropic energy gap in stoichiometric LiFeAs, Physical Review Letters 104 (2010) Nr. 18, S. 187001/1-4 URL

N.Y. Panarina, Y.I. Talanov, T.S. Shaposhnikova, N.R. Beysengulov, E. Vavilova, G. Behr, A. Kondrat, C. Hess, N. Leps, S. Wurmehl, R. Klingeler, V. Kataev, B. Buechner. Pinning effects in ceramic SmO1-xFxFeAs as revealed by microwave absorption, Physical Review B 81 (2010) Nr. 22, S. 224509/1-9 URL

N. Qureshi, Y. Drees, C. Hess, R. Klingeler, B. Büchner, M. T. Fernandez Diaz, M. Braden, Crystal and magnetic structure of the oxypnictide superconductor LaO1-xFxFeAs: evidence for magnetoelastic coupling. Phys. Rev. B 82, 184521 (2010)

2009

H. Luetkens, H.-H. Klauss, M. Kraken, F. J. Litterst, T. Dellmann, R. Klingeler, C. Hess, R. Khasanov, A. Amato, C. Baines, M. Kosmala, O. J. Schumann, M. Braden, J. Hamann-Borrero, N. Leps, A. Kondrat, G. Behr, J. Werner, B. Buechner. The electronic phase diagram of the LaO1-xFxFeAs superconductor, Nature materials 8 (2009) Nr. 4, S. 305-309 URL

H.-J. Grafe, G. Lang, F. Hammerath, D. Paar, K. Manthey, K. Koch, H. Rosner, N. J. Curro, G. Behr, J. Werner, N. Leps, R. Klingeler, H.-H. Klauss, F. J. Litterst, B. Buechner. Electronic properties of LaO1-xFxFeAs in the normal state probed by NMR/NQR, New Journal of Physics 11 (2009) Nr. 3, S. 35002/1-14 URL

Y.G. Ponomarev, S.A. Kuzmichev, M.G. Mikheev, M.V. Sudakova, S.N. Tchesnokov, O.S. Volkova, A.N. Vasiliev, T. Haenke, C. Hess, G. Behr, R. Klingeler, B. Buechner. Andreev spectroscopy of LaFeAsO0.9F0.1, Physical Review B 79 (2009) Nr. 22, S. 224517/1-6 URL

C. Hess, A. Kondrat, A. Narduzzo, J.E. Hamann-Borrero, R. Klingeler, J. Werner, G. Behr, B. Buechner. The intrinsic electronic phase diagram of iron-oxypnictide superconductors, epl 87 (2009) Nr. 1, S. 17005/1-6 URL

A. Kondrat, J.E. Hamann-Borrero, N. Leps, M. Kosmala, O. Schumann, A. Koehler, J. Werner, G. Behr, M. Braden, R. Klingeler, B. Buechner, C. Hess. Synthesis and physical properties of LaO1-xFxFeAs, The European Physical Journal B 70 (2009), S. 461-468 URL

L. Wang, U. Koehler, N. Leps, A. Kondrat, M. Nale, A. Gasparini, A. de Visser, G. Behr, C. Hess, R. Klingeler, B. Buechner. Thermal expansion of LaFeAsO1-xFx: Evidence for high-temperature fluctuations, Physical Review B 80 (2009) 94512

H. Maeter, H. Luetkens, Y.G. Pashkevich, A. Kwadrin, R. Khasanov, A. Amato, A.A. Gusev, K.V. Lamonova, D.A. Chervinskii, R. Klingeler, C. Hess, G. Behr, B. Buechner, H.-H. Klauss. Interplay of rare earth and iron magnetism in RFeAsO (R=La, Ce, Pr, and Sm): Muon-spin relaxation study and symmetry analysis, Physical Review B 80 (2009) Nr. 9, S. 94524/1-19 URL

2008

A. Narduzzo, M.S. Grbic, M. Pozek, A. Dulcic, D. Paar, A. Kondrat, C. Hess, I. Hellmann, R. Klingeler, J. Werner, A. Koehler, G. Behr, B. Buechner. Upper critical field, penetration depth, and depinning frequency of the high-temperature superconductor LaFeAsO0.9F0.1 studied by microwave surface impedance, Physical Review B 78 (2008) Nr. 1, S. 12507/1-4 URL

H.-J. Grafe, D. Paar, G. Lang, N.J. Curro, G. Behr, J. Werner, J. Hamann-Borrero, C. Hess, N. Leps, R. Klingeler, B. Buechner.75As NMR studies of superconducting LaFeAsO0.9F0.1, Physical Review Letters 101 (2008) Nr. 4, S. 47003/1-4 URL

H.-H. Klauss, H. Luetkens, R. Klingeler, C. Hess, F.J. Litterst, M. Kraken, M.M. Korshunov, I. Eremin, S.-L. Drechsler, R. Khasanov, A. Amato, J. Hamann-Borrero, N. Leps, A. Kondrat, G. Behr, J. Werner, B. Buechner. Commensurate spin density wave in LaFeAsO: A local probe study, Physical Review Letters 101 (2008) Nr. 7, S. 77005/1-4 URL

H. Luetkens, H.-H. Klauss, R. Khasanov, A. Amato, R. Klingeler, I. Hellmann, N. Leps, A. Kondrat, C. Hess, A. Koehler, G. Behr, J. Werner, B. Buechner. Field and temperature dependence of the superfluid density in LaFeAsO1-xFx superconductors: A muon spin relaxation study, Physical Review Letters 101 (2008) Nr. 9, S. 97009/1-4 URL

S.A.J. Kimber, D.N. Argyriou, F. Yokaichiya, K. Habicht, S. Gerischer, T. Hansen, T. Chatterji, R. Klingeler, C. Hess, G. Behr, A. Kondrat, B. Buechner. Magnetic ordering and negative thermal expansion in PrFeAsO, Physical Review B 78 (2008) Nr. 14, S. 140503(R)/ 1-4 URL

G. Fuchs, S.-L. Drechsler, N. Kozlova, G. Behr, A. Koehler, J. Werner, K. Nenkov, R. Klingeler, J. Hamann-Borrero, C. Hess, A. Kondrat, M. Grobosch, A. Narduzzo, M. Knupfer, J. Freudenberger, B. Buechner, L. Schultz. High-field pauli-limiting behavior and strongly enhanced upper critical magnetic fields near the transition temperature of an arsenic-deficient LaO0.9F0.1FeAs1- superconductor, Physical Review Letters 101 (2008) Nr. 23, S. 237003/1-4 URL

S.-L. Drechsler, M. Grobosch, K. Koepernik, G. Behr, A. Koehler, J. Werner, A. Kondrat, N. Leps, C. Hess, R. Klingeler, R. Schuster, B. Buechner, M. Knupfer. Optical study of LaO0.9F0.1FeAs: Evidence for a weakly coupled superconducting state, Physical Review Letters 101 (2008) Nr. 25, S. 257004/1-4 URL