APS March Meeting 2012
Volume 57, Number 1
Monday–Friday, February 27–March 2 2012;
Boston, Massachusetts
Session D2: Invited Session: Harnessing Local Atomic Structure to Control Magnetic Interactions in Complex Oxides
2:30 PM–5:30 PM,
Monday, February 27, 2012
Room: 204AB
Sponsoring
Unit:
GMAG
Chair: Steven May, Drexel University
Abstract ID: BAPS.2012.MAR.D2.1
Abstract: D2.00001 : Interface engineering in manganites: from diodes to transistors
2:30 PM–3:06 PM
Preview Abstract
Abstract
Author:
Harold Hwang
(Stanford University and SLAC National Accelerator Laboratory)
Perovskite manganites show strong coupling between charge, spin, and lattice
degrees of freedom as exemplified by `colossal magnetoresistance'. The
recent advances in thin film growth techniques have enabled the generation
of novel phases at oxide heterointerfaces, the atomic control of their
interface electronic structure, and their incorporation in novel device
platforms. We apply these techniques to manganite thin films, first
emphasizing the subtleties in optimizing the growth kinetics and
stoichiometry [1,2], which has enabled us to create atomically precise
heterostructures exhibiting room temperature metallic ferromagnetism in
superlattices composed of just 5 unit cell layers [3]. The interface
electronic structure was examined using Schottky junctions formed between
La$_{0.7}$Sr$_{0.3}$MnO$_{3}$ and Nb-doped SrTiO$_{3}$, where the band
offset (Schottky barrier height) can be controlled by the termination layer
at the interface [4]. This band engineering technique was applied in making
a metal-base transistor [5], which takes advantage of the strong internal
electric field at interfaces. An analysis of many devices enables the
quantitative understanding of the evolution from a hot-electron transistor
to a permeable base transistor. This structure provides a platform for
developing devices incorporating the exotic ground states of perovskite
oxides and their interfaces.
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[1] J. H. Song, T. Susaki, and H. Y. Hwang, \textit{Adv. Mater.} \textbf{20}, 2528 (2008).
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[2] D. A. Muller, L. Fitting Kourkoutis, M. Murfitt, J. H. Song, H. Y.
Hwang, J. Silcox, N. Delby, and O. L. Krivanek, \textit{Science} \textbf{319}, 1073 (2008).
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[3] L. Fitting Kourkoutis, J. H. Song, H. Y. Hwang, and D. A. Muller, \textit{PNAS}
\textbf{107}, 11682 (2010).
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[4] Y. Hikita, M. Nishikawa, T. Yajima, and H. Y. Hwang, \textit{Phys. Rev. B} \textbf{79},
073101 (2009).
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[5] T. Yajima, Y. Hikita, and H. Y. Hwang, \textit{Nature Mater.} \textbf{10}, 198 (2011).
To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2012.MAR.D2.1