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)
Ran S; Bud'ko S L; Pratt D K; Kreyssig A; Kim M G; Kramer M J; Ryan D H; Rowan-Weetaluktuk W N; Furukawa Y; Roy B; Goldman A I; Canfield P C . 2011. Stabilization of an ambient-pressure collapsed tetragonal phase in CaFe(2)As(2) and tuning of the orthorhombic-antiferromagnetic transition temperature by over 70 K via control of nanoscale precipitates. Physical Review B. 83:144517.
Bulaevskii L N; Graf M J; Batista C D; Kogan V G . 2011. Vortex-induced dissipation in narrow current-biased thin-film superconducting strips. Physical Review B. 83:144526.
Ryan D H; Rowan-Weetaluktuk W N; Cadogan J M; Hu R; Straszheim W E; Bud'ko S L; Canfield P C . 2011. Fe-57 Mossbauer study of magnetic ordering in superconducting K0.80Fe1.76Se2.00 single crystals. Physical Review B. 83:104526 .
Mun E D; Altarawneh M M; Mielke C H; Zapf V S; Hu R; Bud'ko S L; Canfield P C . 2011. Anisotropic Hc2 of K0.8Fe(1.76)Se(2) determined up to 60 T. Physical Review B. 83:100514.
Lu X; Park W K; Yeo S; Oh K H; Lee S I; Bud'ko S L; Canfield P C; Greene L H . 2011. Superconducting order parameter in nonmagnetic borocarbides RNi2B2C (R = Y, Lu) probed by point-contact Andreev reflection spectroscopy. Physical Review B. 83:104519 .
Maniv A; Maniv T; Zhuravlev V; Bergk B; Wosnitza J; Kohler A; Behr G; Canfield P C; Sonier J E . 2011. Damping of de Haas-van Alphen oscillations and vortex-lattice disorder in the peak-effect region of extreme type-II borocarbide superconductors. Physical Review B. 83:104505.
Ryan D H; Lee-Hone N R; Cadogan J M; Canfield P C; Bud'ko S L . 2011. Magnetic ordering in GdAgSb2. Journal of Physics-Condensed Matter. 23:106003.
Kim H; Tanatar M A; Song Y J; Kwon Y S; Prozorov R . 2011. Nodeless two-gap superconducting state in single crystals of the stoichiometric iron pnictide LiFeAs. Physical Review B. 83:100502.
Hodovanets H; Mun E D; Thaler A; Bud'ko S L; Canfield P C . 2011. Thermoelectric power of Ba(Fe1-xRux)(2)As-2 and Ba(Fe1-xCox)(2)As-2: Possible changes of Fermi surface with and without changes in electron count. Physical Review B. 83:094508.