1. Condensed-Matter Physics & Materials Science Seminar

    "Understanding the Metal-Mott Insulator Crossover"

    Presented by Yue Cao, University of Colorado

    Wednesday, January 8, 2014, 1:30 pm
    ISB Bldg. 734, Conf. Room 201 (upstairs)

    Hosted by: John P. Hill

    How Mott insulators acquire metallicity upon the introduction of extra carriers lies at the heart of correlated electron physics. Investigating the evolution of the electronic structure and low energy dynamics during the insulator breakdown provides critical evidence concerning the "fingerprint" of metal-Mott insulator crossover, and may also help address the global phase diagram of the doped Mott insulators. In this talk, I report ARPES studies of the Rh and La doped Sr2IrO4 and show the emergence and evolution of pseudogaps and Fermi arcs. The experimental results in the doped iridates resemble those observed in the cuprate systems, which are prototype Mott insulators. Due to a cleaner phase diagram (compared to cuprates) we could rule out instabilities including long-range order and density wave formation and argue that short-range correlation is responsible for many of the observed exotic phenomenon. At the end of the talk, I would like to propose how designed scattering experiments could advance our understanding of the metal- Mott insulator crossover.