Complex States, Emergent Phenomena & Superconductivity in Intermetallic & Metal-like Compounds
Kyuil Cho, Abhishek Pandey
The specific scientific question to be addressed by this Project is—can we develop, discover, understand and ultimately control, and predictably modify new and extreme examples of complex states, emergent phenomena, and superconductivity? Materials manifesting clear or compelling examples (or combinations) of superconductivity, strongly correlated electrons, quantum criticality, and exotic, bulk magnetism are of particular interest given their potential to lead to revolutionary steps forward in our understanding of their complex, and potentially energy relevant, properties. Experiment and theory are implemented synergistically. The experimental work consists of new materials development and crystal growth, combined with detailed and advanced measurements of microscopic, thermodynamic, and transport properties, as well as electronic structure, at extremes of pressure, temperature, magnetic field and resolution. The theoretical work focuses on modeling transport, thermodynamic and spectroscopic properties using world-leading, phenomenological approaches to superconductors and modern quantum many-body theory.
The ability to address these questions is illustrated by this group’s past work on many of the key systems and phenomena that have defined this field over the past decades: High Tc oxide, RNi2B2C and MgB2 superconductivity, Ce-, Yb- and transition metal-based heavy fermions, quantum criticality, quasicrystals, spin glasses, spin ladders / spin chains, vortex and domain pattern formation, ferromagnetism and metamagnetism.
- Design and growth (P. C. Canfield, S. Bud’ko, D. C. Johnston, J. Schmalian,V. Kogan)
- Advanced Characterization (S. Bud’ko, Y. Furukawa, A. Kaminski, R. Prozorov, M. Tanatar)
- Theory and modeling (J. R. Clem, V. Kogan, J. Schmalian)
Aczel A A; Baggio-Saitovitch E; Budko S L; Canfield P C; Carlo J P; Chen G F; Dai P C; Goko T; Hu W Z; Luke G M; Luo J L; Ni N; Sanchez-Candela D R; Tafti F F; Wang N L; Williams T J; Yu W; Uemura Y J . 2008. Muon-spin-relaxation studies of magnetic order and superfluid density in antiferromagnetic NdFeAsO, BaFe2As2, and superconducting Ba1-xKxFe2As2. Physical Review B. 78:214503.
Belashchenko K D; Antropov V P . 2008. Role of covalent Fe-As bonding in the magnetic moment formation and exchange mechanisms in iron-pnictide superconductors. Physical Review B. 78:212505.
Prozorov R; Ni N; Tanatar M A; Kogan V G; Gordon R T; Martin C; Blomberg E C; Prommapan P; Yan J Q; Bud'ko S L; Canfield P C . 2008. Vortex phase diagram of Ba(Fe0.93Co0.07)(2)As-2 single crystals. Physical Review B. 78:224506.
McQueeney R J; Diallo S O; Antropov V P; Samolyuk G D; Broholm C; Ni N; Nandi S; Yethiraj M; Zarestky J L; Pulikkotil J J; Kreyssig A; Lumsden M D; Harmon B N; Canfield P C; Goldman A I . 2008. Anisotropic Three-Dimensional Magnetism in CaFe2As2. Physical Review Letters. 101:227205.
Reibelt M; Schilling A; Canfield P C; Ravikumar G; Berger H . 2008. Differential-thermal analysis around and below the critical temperature T-c of various low-T-c superconductors: A comparative study. Physica C-Superconductivity and Its Applications. 468:2254-2266.
Khasanov R; Kondo T; Strassle S; Heron D O G; Kaminski A; Keller H; Lee S L; Takeuchi T . 2008. Evidence for a Competition between the Superconducting State and the Pseudogap State of (BiPb)(2)(SrLa)(2)CuO6+delta from Muon Spin Rotation Experiments. Physical Review Letters. 101:227002.
Vannette M D; Prozorov R . 2008. Field-dependent AC susceptibility of itinerant ferromagnets. Journal of Physics-Condensed Matter. 20:475208.
Kreyssig A; Green M A; Lee Y; Samolyuk G D; Zajdel P; Lynn J W; Bud'ko S L; Torikachvili M S; Ni N; Nandi S; Leao J B; Poulton S J; Argyriou D N; Harmon B N; McQueeney R J; Canfield P C; Goldman A I . 2008. Pressure-induced volume-collapsed tetragonal phase of CaFe2As2 as seen via neutron scattering. Physical Review B. 78:184517.
Martin C; Vannette M D; Gordon R T; Prozorov R; Karpinski J; Zhigadlo N D . 2008. Effect of C and Li doping on the rf magnetic susceptibility in MgB2 single crystals. Physical Review B. 78:144512.