"Emergent Phenomena in Complex Oxide Heterostructures" by Susanne Stemmer (UC Santa Barbara)

Thursday, October 6, 2016 - 4:00pm to 5:00pm
Physics and Astronomy Colloquium

Thursdays, 4:00-5:00 pm

1-434 Physics and Astronomy (map)
Reception from 3:30-4:00 p.m.
(unless otherwise posted)


Guest Speaker: Susanne Stemmer (University of California, Santa Barbara)

Talk Title:  “Emergent Phenomena in Complex Oxide Heterostructures”


Understanding the origins of the unique properties and phase behavior of strongly correlated materials is one of the most significant challenges in materials physics.  In this talk, we discuss how complex oxide heterostructures allow for new approaches to probe, control, and understand strong correlation phenomena.  We will discuss a specific materials system, namely, thin films of the rare earth nickelates, which exhibit a wealth of correlated phenomena, including different types of metal-insulator transitions (MITs) and non-Fermi liquid behavior.  We show that these can be tuned via strain and film thickness.  Accounting for resistance saturation clarifies many aspects of their phase behavior and the quantum critical point in the system.  To understand the microscopic origins, we use convergent beam electron diffraction in scanning transmission electron microscopy to characterize strained films both above and below the MIT.  We show that a symmetry lowering structural change takes in films that undergo an MIT, but is absent otherwise.  Using space group symmetry arguments, we show that these results provide a remarkably simple understanding of the MIT as well as insights into the non-Fermi liquid phase that is observed in films for which the MIT is absent.  If time permits, we will also discuss another oxide heterostructure system, namely high-density electron liquids in confined SrTiO3 structures.


For more information, contact Jay Hauser

We thank the following people for their contributions to the wine fund for the post-colloquium reception:
Prof. Dolores Bozovic, Prof. Mike Cornwall, Prof. Bob Cousins, Prof. Andrea Ghez, Prof. Karoly Holczer, Prof. Eric Hudson, Robert Huff, Prof. Alex Kusenko, Prof. Myank Mehta, Prof. John Miao, Prof. Roberto Peccei, Prof. Claudio Pellegrini, Prof. David Saltzberg, Prof. Jean Turner and Prof. Ben Zuckerman.

1-434 PAB