APS March Meeting 2012
Volume 57, Number 1
Monday–Friday, February 27–March 2 2012;
Boston, Massachusetts
Session A20: Invited Session: Advanced Quantum Materials for Future Information Technology
8:00 AM–11:00 AM,
Monday, February 27, 2012
Room: 253C
Sponsoring
Unit:
FIAP
Chair: Cherry Murray, Harvard University
Abstract ID: BAPS.2012.MAR.A20.3
Abstract: A20.00003 : Quantum information processing with defect spins in diamond and silicon carbide*
9:12 AM–9:48 AM
Preview Abstract
Abstract
Author:
William Koehl
(Center for Spintronics and Quantum Computation, University of California, Santa Barbara, CA 93106 USA)
Many proposals for quantum information technologies require quantum systems
that can be easily manipulated by an outside observer, while remaining
largely unaffected by destructive interactions with the surrounding
environment. One system that matches this description is a defect in the
crystal lattice of diamond known as the nitrogen-vacancy (NV) center.
Electrons trapped at this defect form an atomic scale spin state that can be
used as an individually addressable, solid state quantum bit (qubit) even at
room temperature. The exceptional quantum properties of the diamond NV have
motivated recent efforts to search for similar defects in other
semiconductors, as these would expand the technological opportunities
available to defect-based quantum systems [1]. We discuss these efforts,
which make use of techniques from both computational materials science and
experimental quantum physics, focusing on explorations of the 4H polytype of
silicon carbide (4H-SiC). In particular, we present recent experimental
results that identify several defect spin states in 4H-SiC that function as
analogs to the diamond NV. Using optical and microwave techniques similar to
those used with diamond NV qubits, the spins of these defects can be
optically addressed and coherently controlled in the time domain at
temperatures ranging from 20 -- 300 K. Additionally, these defects are
optically active near telecom wavelengths, inhabit a host material for which
there already exist industrial scale crystal growth and advanced
microfabrication techniques, and possess desirable spin coherence properties
comparable to those of the diamond NV. This makes them promising candidates
for various photonic, spintronic, and quantum information applications that
merge quantum degrees of freedom with classical electronic and optical
technologies [2].
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{[1]} J. R. Weber*, W. F. Koehl*, J. B. Varley*, A. Janotti, B. B. Buckley, C.
G. Van de Walle, and D. D. Awschalom, \emph{Proc.~Natl~Acad.~Sci.~USA} \textbf{107}, 8513
(2010).\\
{[2]} W. F. Koehl, B. B. Buckley, F. J. Heremans, G. Calusine, and D. D.
Awschalom, \emph{Nature} \textbf{479}, 84 (2011); A. Dzurak, \emph{Nature} \textbf{479}, 47 (2011).
*This work is funded by AFOSR and DARPA.
To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2012.MAR.A20.3