Slideshow - Physics at the University Of Virginia

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Quantum manipulation of NV centers in
diamond
12.09.2014
The University of Virginia
Physics Colloquium
Alex Retzker
Jianming Cai, Andreas Albrect, M. B. Plenio,Fedor Jelezko, P.
London, R. Fisher,B. Nayedonov, L. Mcguiness, Guy Koplovitz, Shira
Yochelis,Danny Porath, Yuval Nevo, Oded Shoseyov, Yossi Paltiel,
Paz London. Ran Fischer
NJP 15 013020 (2013), Nature Physics 9, 168 (2013)
PRL. 111, 067601 (2013), NJP. 16 093002 (2014)
BOSCH UND SIEMENS HAUSGERÄTE GRUPPE
Quantum computing/Simulations
Scanning probe
magnetometer
P. Neumann et al., Science 329, 542 (2010)
Quantum devices and
photonics
G. Balasubramanian, et al. Nature 455, 648 (2008)
J.Maze, et al, Nature 455, 644 (2008)
R. Kolesov et al. Nat. Phys. 5, 470
(2009)
Nanodiamonds for cellular imaging
NV in diamond
Biosensor technology &
Molecular Spin sensors
L. C. L. Hollenberg, et al, Nature Nanotec 6, 358
(2011).
Diamond
5m
The Color is given by the
color centers
Isotope: 99.998%
12C
CVD reactor: University Paris XIII
(Villtaneuse) J. Achard
Concentration of impurities:
below 1012 cm-3 (optical resolution)
D. Twitchen, Element 6 Ltd
Virginia Physics Colloquium I 12.09.2014 I Folie: 3
Color Centers
Nitrogen-Vacancy color centerexcited E
3
state
1A
3A
ground
state
Optical excitation: read out and
initialization: 96%
mS = ±1
mS = 0
} e-spin
Early work: Manson, Glasbeek, Hemmer (ensembles)
Single center detection Gruber A et al., Science 276 2012 (1997)
Single spin deteciton
Fluorescence, a. u.
Fluorescence [a.u.]
A
Ambient condition =
Room temperature!
No vacuum!
Laser
30 %
2800
APD
ESR of
single N-V
defect
3000
MW frequency,
frequency [MHz]
MW
MHz
Single NV-Centers
Diamond
surface
Microwave and
Radiofrequency
A
I
time
fluorescence intensity [a.u.]
Coherent control
/2


0,00
mS=+1
-1
0,05
microwave pulselength  [s]
0,10
Jelezko et al., PRL 2004, Epstein Nat. Phys
(2005), Childress Science (2006) …
up to GHz control, Fuchs et al., Science 326, 1520
(2009)
MW
mS=0
figure of merit:
• Phase memory time T2*=110µs, T2=2.6 ms (e6)
 ultrapure CVD diamonds (no electron spins)
• 106 Rabi oscillations within T2
Single shot readout single nuclear spin
Repetitive QND measurements reveal quantum jumps of a
single nuclear spin (in diamond at room temperature)
Neumann et al., Science 2010
Ramsey magnetometer
-
Zeeman Shift
¯ + e iwt ¯
Measurement
error
Total time
Coherence time
NV center in diamond as a nano-scale quantum sensor
o Chemical and thermal stability
o Optical readout of spin state
o Coherent control with microwave
o Long coherence time: spin bath
o Non-toxic: biological/medical application
How to detect a single nucleus?
o Long measurement time: small magnetic moment
o Single out the target nucleus from environment noise
J. R. Maze, et al, Nature 455, 644 (2008).
G. Balasubramanian, et al, Nature 455, 648 (2008).
Our proposal: Continuously driven diamond spin sensor
Single molecule magnetic resonance spectroscopy
Decoherence of NV centers in diamond
NV Center
paramagnetic spin-1/2 nitrogen donors
13C
isotopic impurity spin-1/2 nuclear spins
SIGNAL
NV in diamond
Measure position of a single nucleus: Idea
(
)
A = g 3rz2 +1 ĥ (q 0 , f0 )
r × r̂
Prob
e
Direction
of the field
Dipole - Dipole
o Flip-flop process between NV sensor and target system
1 1
S(t) = + éë1+ cos ( Jt )ùû
2 4
J=
(
1é
g(r) 3rz2 +1 ù 1- ĥ × b̂
û
4ë
)
Experimental setup and procedure
• Magnetic Field of 0.54T. Nuclear 13C
energy scale (Larmor frequency) at
this field is ~6MHz.
• We apply the spin-locking sequence.
• The sequence is repeated ~105 times
to average photons statistics.
Initialize NV
center’s spin
light
Microwave
Let the spins
interact
Readout NV
center’s spin
Experiment
Experiment
Precision of 0.5 Angstrom
Experiment
Detecting and polarizing nuclear spins
Experimental results
IPL (Rabi-normalized)
Outside the double resonance, the
NV center’s spin is locked and
decoupled from the environment
0.5
0.4
0.3
0.2
0.1
At resonance, we witness
oscillations of population
between the spins.
0
0
18
5
10
15
20
Locking time (sec)
25
Polarizing Nuclei using Hartmann-Hahn sequence
Polarization –Direct measurements
We can actually play with polarization
by controlling the rates of the two
sequences
Alternating
Or
Polarize
/2
[s]
/2
Detecting and polarizing nuclear spins
Analong Quantum simulator
Proposed by Feynman
in 1982
Much easier than a
quantum computer
since does not require
the usual error
correction but a
simplified version of
it?
Virginia I 12.09.2014 I Folie: 22
Digital Quantum Simulator
Seth Lloyd
1996
The idea behind this is the
trotter decomposition and BCH
For two noncommuting
operators
e ieH1 e -ieH 2 ¹ e ie ( H1 - H 2 )
However in the limit:
Coherent control:
eH1 +eH 2
e
eH1 eH 2
=e e e
-
e2
2
[ H1 ,H 2 ]
e 3 ()
e
...
Virginia I 12.09.2014 I Folie: 23
Quantum Simulator: spin arrays
Single spin readout
Coherent interaction
Magnetic dipole coupled spin arrays
B
dip
 0 

  3cos 2   1 r 3
 4 
Challenge: creation and addressing single qubits
Bulck Diamond
Precision is
limited by
1μm with
regular
implantation
However, for dipole dipole interaction a distance of 10
nm is necessary
Diamond-based quantum simulator: architecture
Wolfgang Pauli: “God made the bulk;
the surface was invented by the devil”
Fluorine nuclear spins (directly linked to
diamond or linked to a graphene sheet)
Electron and nuclear spin arrays in
diamond (P donor, 13C)
NV center in nuclear spin free 12C diamond
J.-M. Cai, AR , Fedor Jelezko, Martin B. Plenio, Nature Physics 9, 168 (2013)
Diamond-based quantum simulator: architecture
(a) (111) surface
ga=6.8kHz
(b) (100) surface
J.-M. Cai, , Fedor Jelezko, Martin B. Plenio, Nature Physics 9, 168 (2013)
Nuclear spin quantum simulator on diamond surface
! $#
&! ' #( ) #
%" #
%
*! +#( ) #
±1
!" #
0
Rothemund’s idea: DNA origami
Nature, 440, (2006)
Virginia Physics ColloquiumI 12.09.2014 I Folie: 30
DNA origami and gold
Figure 1. Assembly of DNA origami gold particle NP assembly is composed of nine 10 nm gold partic
helix bundle. Each NP attachment site consists of th
gold nanoparticles carrying multiple thiol‐modified
mixed with the assembled 24‐helix bundles and gel‐
left‐handed gold nanohelices (Scale bar: 100 nm). difference in absorbance (∆A) between left‐handed c
(RCP) of varying wavelengths through a cuvette con
handed) is recorded. ∆A is represented as CD signal Virginia Physics ColloquiumI 12.09.2014 I Folie: 31
SP1 and gold
Oded Shoseyov and Danny Porath
SP1 and NV
Andreas Albrecht, AR, Guy Koplovitz, Fedor Jelezko, Shira Yochelis,
Danny Porath, Yuval Nevo, Oded Shoseyov, Yossi Paltiel, and Martin
B Plenio arxiv:1301.1871
The Spin lattice
noise
decoupling
Dipolar coupling
Coherence
time
Rabi frequency of
driving/ decoupling
In principle very versatile as a large set of Hamiltonians could be created digitally
Summary
🍁 NV probe for measuring nuclear spin states – Quantum microscope
☞ Readout a single nuclear (electron) spin state: quantum information processing
🔱 Selective coupling
🔱 Sensitivity limit : approaching to T1
☞ Probe many-body physics: towards a large-scale quantum simulator
🔱 A new platform based on NVs for quantum simulations
🔱 Complementary advantages to the other physical systems
Thank you!
BOSCH UND SIEMENS HAUSGERÄTE GRUPPE

Slideshow - Physics at the University Of Virginia

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