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VERSION:2.0
CALSCALE:GREGORIAN
PRODID:UW-Madison-Physics-Events
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SEQUENCE:0
UID:UW-Physics-Event-4456
DTSTART:20170504T150000Z
DURATION:PT1H0M0S
DTSTAMP:20240329T121436Z
LAST-MODIFIED:20170426T113547Z
LOCATION:5310 Chamberlin
SUMMARY:Coherent defects in diamond\, R. G. Herb Condensed Matter Semi
nar\, Nathalie de Leon\, Princeton
DESCRIPTION:Engineering coherent systems is a central goal of quantum
science and quantum information processing. Point defects in diamond k
nown as color centers are a promising physical platform. As atom-like
systems\, they can exhibit excellent spin coherence and can be manipul
ated with light. As solid-state defects\, they can be produced at high
densities and incorporated into scalable devices. Diamond is a unique
ly excellent host: it has a large band gap\, can be synthesized with s
ub-ppb impurity concentrations\, and can be isotopically purified to e
liminate magnetic noise from nuclear spins. Specifically\, the nitroge
n vacancy (NV) center has been used to has been used to demonstrate ba
sic building blocks of quantum networks and quantum computers\, and ha
s been demonstrated to be a highly sensitive\, non-invasive magnetic p
robe capable of resolving the magnetic field of a single electron spin
with nanometer spatial resolution. However\, realizing the full poten
tial of these systems requires the ability to both understand and mani
pulate diamond as a material. I will present two recent results that d
emonstrate how carefully tailoring the diamond host can dramatically i
mprove the performance of color centers for various applications.
\nFirst\, currently-known color centers either exhibit long spin coher
ence times or efficient\, coherent optical transitions\, but not both.
We have developed new methods to control the diamond Fermi level in o
rder to stabilize a new color center\, the neutral charge state of the
silicon vacancy (SiV) center\, which exhibits both the excellent opti
cal properties of the negatively charged SiV center and the long spin
coherence times of the NV center\, making it a promising candidate for
applications as a single atom quantum memory for long distance quantu
m communication.
\nSecond\, color centers placed close to the diam
ond surface can have strong interactions with molecules and materials
external to the diamond. However\, uncontrolled surface termination an
d contamination can degrade the color center properties and give rise
to noise that obscures the signal of interest. I will describe our rec
ent efforts to stabilize shallow NV centers within 5 nm of the surface
using new surface processing and termination techniques. These highly
coherent\, shallow NV centers will provide a platform for sensing and
imaging down to the scale of single atoms.
\n
URL:https://www.physics.wisc.edu/events/?id=4456
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