Binghamton University
Department of Physics, Applied Physics and Astronomy
PHYSICS COLLOQUIUM
“Emergent quantum phases from nanoscale confinement of correlated
transition-metal oxides”
Dr. Phil King
University of St. Andrews
Abstract:
Hosting strong interactions and rich resulting phase diagrams, correlated transition-metal oxides
present enormous promise for future multifunctional electronic devices. Artificially confining their
electrons to dimensions on the order of the de Broglie wavelength represents a new frontier for the
design of novel quantum materials, but understanding how their collective electronic phases can be
rationally manipulated at an atomic scale remains a formidable challenge. In this talk, I will present
two examples of the creation and control of nanoscale electron systems in transition-metal oxides,
while simultaneously probing the evolution of their electronic structure using angle-resolved
photoemission. First, I will demonstrate how a two-dimensional electron gas (2DEG) can be created at
the bare surface of the band insulator SrTiO3 via control of its surface stoichiometry. This is
analogous to the 2DEG at the heart of the ubiquitous semiconductor transistor, but I will demonstrate
how charge-, spin-, orbital-, and lattice degrees of freedom become strongly entangled in the oxide
case. Second, I will show how the correlated metal LaNiO3- can be tuned from a metal to an insulator
by confining its thickness to just two unit cells (<1nm), driven by an instability to an incipient order of
the underlying quantum many-body system. Together, these reveal new ways to harness control over
competing interactions and subtle quantum phases in complex oxides.
Monday, November 11, 2013
Science Library Room 212
PRESENTATION BEGINS AT 11:00 AM
ALL ARE WELCOME – COFFEE AND REFRESHMENTS AT 10:45am