Ultrafast infrared nano-spectroscopy and nano-imaging of unconventional superconductivity in cuprate and pnictide high-Tc systems [electronic resource]

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Bibliographic Details
Online Access: Online Access (via OSTI)
Format: Government Document Electronic eBook
Language:English
Published: Washington, D.C. : Oak Ridge, Tenn. : United States. Department of Energy. ; distributed by the Office of Scientific and Technical Information, U.S. Department of Energy, 2019.
Description
Abstract:High-Tc superconductivity is surpassed by few, if any, other unsolved problems in contemporary physics in terms of its richness, complexity, impact on other fields, and potential technological importance. Before 2008, the term "high-Tc superconductivity" was reserved for copper oxides or cuprates (maximum Tc̃160 K). The discovery of superconductivity in Fe-based pnictides compounds with Tc almost as high as 60 K has prompted a renewed surge of research activity. Systematic studies have revealed both common and contrasting trends in the cuprate and pnictide superconductors. In both classes of materials, superconductivity occurs in close proximity with other electronic phases: an antiferomagnetic (AF) Mott insulator state in the case of the (hole-doped) cuprates and metallic spin density wave (SDW) phase in the case of the pnictides. One common aspect of Fe- and Cu-based systems is a propensity towards electronic and magnetic self-organization, leading to dynamic inhomogeneities at nano-to-mesoscopic length scales. The inhomogeneities have so far been documented with quasi-static probes such as nuclear magnetic resonance, neutron and x-ray scattering along with scanning tunneling microscopies. In contrast, ultrafast infrared/optical studies enable characterization of dynamics and fluctuations in superconductors. However, such experiments have been carried out using diffraction-limited optics and therefore probe length scales that inform us of a "mixed" response involving contributions from the multiple electronic, chemical and structural phases occurring in real materials while averaging over nanoscale heterogeneities. As a result, the interpretation of area-averaged ultrafast optics data has often remained both complicated and ambiguous.
Item Description:Published through SciTech Connect.
02/20/2019.
"final technical"
DMITRI BASOV; RICHARD AVERITT; MICHAEL FOGLER; JAMES HONE; ANDREW MILLIS.
UC San Diego.
Type of Report and Period Covered Note:Final;