1. ULTRA-PRECISE CLOCK SYNCHRONIZATION VIA DISTANT ENTANGLEMENT
Selim Shahriar, Project PI
Franco Wong, Co-PI
Res. Lab. Of Electronics
DARPA QUantum Information Science
and Technology
May 2004 / Chicago
Selim Shahriar, subcontract PI
Dept. of Electrical and Computer Engineering
Laboratory for Atomic and Photonic Technologies
Center for Photonic Communications and Computing
Ulvi Yurtsever, “subcontract” PI
Jet Propulsion Laboratory
Dr. Marco Fiorentino,
Dr. Frieder Konig,
Taehyun Kim (GS)
Dr. George Cadoso
Dr. Prabhakar Pradhan
Dr. Venkatesh Gopal
Dr. Gaur Tripathi
Ken Salit (GS)
Jacob Morzinski (GS)
Ahmed Hasan (US)
Dr. John Dowling
Dr. Chris Adami
Dr. Robert Gringich
Dr. Attila Bergou
Dr. Hwang Lee
Dr. Demetri Strekalov

2. D t PROJECT ELEMENTS D f POTENTIAL BENEFIT TIMELINE OF EFFORT
POGRAM SUMMARY
D t
Picosecond scale synchronization of separated clocks,
and remote frequency-locking will increase the resolution
of GPS systems
Quantum memory will be produced with a coherence time
of upto several minutes, making possible high-fidelity
quantum communication and teleportation
Sub-pico-meter scale resolution measurement of amplitude
as well as phase of oscillating magnetic fields would enhance
the sensitivity of tracking objects such as submarines
Non-deg Teleportation
Bloch-Siegert Oscillation
Frequency Teleportation
Relativist Entanglement
Decoherence in Clock-Synch
YR1
YR3
YR2
Entangled Photon Source
CLOCK A
CLOCK B
D f
TRAPPED RB ATOM QUANTUM MEMORY
ULTRA-BRIGHT SOURCE FOR ENTANGLED
PHOTON PAIRS
DEGENERATE DISTANT ENTANGLEMENT
BETWEEN PAIR OF ATOMS
QUANTUM FREQUENCY TELEPORTATION VIA
BSO AND ENTANGELEMENT
RELATIVISTIC GENERALIZATION OF
ENTANGLEMENT AND FREQUENCY TELEPORTATION
SUB-SHOT-NOISE TIME SIGNALING VIA ENTANGLED
FREQUENCY SOURCE
POTENTIAL BENEFIT
PROJECT ELEMENTS
TIMELINE OF EFFORT
Entanglement variation can be used to account for
Relativistic ---including Doppler --- effect without
Having to measure velocity separately, thus increasing
Accuracy of Time Transfer

3. A t t t1 t2 t x x THE BLOCH-SIEGERT OSCILLATION 3 1
“Driver Phase Correlated Fluctuations in the Rotation of a Strongly Driven Quantum Bit," M.S. Shahriar, P. Pradhan, and J. Morzinski, to appear in Phys. Rev. A

4. KEY STEP OF PROTOCOL: USE BSO SIGNATURE TO TELEPORT PHASE INFORMATION3 3 A B 1 2 1 2
ALICE: t1 t2
2 - 3
1 - 3 t t5 t6 t3 t4 t7 t8
1 - 3
BOB:
2 - 3 t

5. BOB RESULT OF THE PROTOCOL: Df
BOB
“Physical Limitation to Quantum Clock Synchronization,” V. Giovanneti, L. Maccone, S. Lloyd, and M.S. Shahriar, Phys. Rev. A 65, (2002)
“Wavelength Teleportation via Distant Quantum Entanglement Using the Bloch-Siegert Oscillation ” M.S. Shahriar,
P. Pradhan, V. Gopal, J. Morzinski, G. Cardoso, and G.S. Pati under review for Physical Review Letters

6. EXPT APPARTUS FOR OBSERVATION OF BSO USING RB ATOMIC BEAM
0.35 mm
hole Rb
Oven
1 mm
~1 mm
Liquid N2 Cold Trap
4.5 mm
7 mm
16.5 mm
RF coil
Nozzle
Collimator
~15 cm
Fluorescence
Imaging lens u
B(t)
Atomic beam
Optical
pumping
APD
Probe beam
EXPT APPARTUS FOR OBSERVATION OF BSO USING RB ATOMIC BEAM
USE ZEEMAN SUBLEVELS
THERMAL VELOCITY SPREAD DOES
NOT CAUSE BSO WASHOUT
REASON: BSO MAPS PHASE AS SEEN
BY AN ATOM AT THE LOCATION AND
TIME IT IS DETECTED --- VIA
FLUORESCENCE

7. BSO FOR AN RF-EXCITED THREE LEVEL SYSTEM

8. EXPERIMENTAL SETUP FOR ANALYZING RABI-FLOPPING AND BSO

9. DIRECT OBSERVATION OF THE BSO AT 2 IN REAL TIME
trigger
Atomic Beam
Probe Laser
Lens
APD RF
RF source
frequency
doubler
oscilloscope
signal
F=2
F=1 RF
F=0
When I block the light , signal goes away and I shine light directly on the APD the signal is flat.

10. DIRECT, LOCALIZED MEASUREMENT OF PHASE OF RF FIELD
trigger
Atomic Beam
Probe Laser
Lens
APD RF
RF source
frequency
doubler
oscilloscope
signal
0.4T delay line (a)
DIRECT, LOCALIZED MEASUREMENT OF PHASE OF RF FIELD
“In-Situ Observation of the Absolute Phase of a Microwave Field
via Incoherent Fluorescence Detection" G. Cardoso, P. Pradhan,
and M.S. Shahriar, under review for Nature.

11. DEMONSTRATION THAT THE SIGNAL IS NOT FROM A PICK-UP
Atomic Beam
Probe Laser
Lens
APD RF
Bo sin (wt +f)

12. TRAPPED ATOM FOR REMOTE ENTANGLEMENT
TSL1
IMAGE
INTENSIFIED
CCD CAMERA
DET
FIBER
FORT

13. TWO SEPARATE TRAPS FOR ALICE AND BOB
“Long Distance, Unconditional Teleportation of Atomic States Via Complete Bell State Measurements,” S. Lloyd, M.S. Shahriar, J.H. Shapiro and P.R. Hemmer, Phys. Rev. Letts.87, (2001)

14. A SINGLE-ZONE, CONTINUOUS ATOM-INTERFEROMETERw1 w2
“Continuously Guided Atomic Interferometry Using a Single-Zone Optical Excitation: Theoretical Analysis," M.S. Shahriar,
M. Jheeta, Y. Tan, P. Pradhan, and A. Gangat, under review for Physical Review A.

15. A SINGLE-ZONE, CONTINUOUS ATOM-INTERFEROMETERw1 w2
|b>
|a>

16. DEMONSTRATION OF THE SINGLE-ZONE, CONTINUOUS ATOM-INTERFEROMETER
3035 MHz
121 MHz
F=3
F=2 D OP R1 R2
F’=4
F’=3
MHz
GALVO
SCANNER
PMT A B
Atom Interferometer
M-Z Interferometer
Phase Scan
Rotation at rate  causes fringe minimum to shift by  
“Demonstration Of A Continuously Guided Atomic Interferometer Using A Single-Zone Optical Excitation,"
M.S. Shahriar, Y. Tan, M. Jheeta, J. Morzinksy, P.R. Hemmer and P. Pradhan, under review for Phys. Rev. Letts

17. |> = Cos(/2)|A> |1> + Sin(/2)|E> |0>
THE SINGLE-ZONE INT REVISITED: TWO-LEVEL MODEL
|e, k >=|E>
|> = |A> |1>
At Start: w
After Excitation:
|a, 0>=|A>
|> = Cos(/2)|A> |1> + Sin(/2)|E> |0>
 = 2  U m / 
* Replace 2-lev with 3-lev system in practice
** Replace single atom with ensemble possibly 
“Single-Photon, Single-Atom Interferoemetry for Entangling Macroscopic Rotors,“M. S. Shahriar, P. Pradhan, and R. Nair
to be submitted to Phys. Rev. Letts.

18. SINGLE-ZONE ATOM-INTERFEROMETRY FOR FREQUENCY LOCKING
|b> A+ A-
A-Clock A 
Alice A
Post-Selection Correlation: Cos[x (WB-WA) ]
EPP-Source
Enables Asynchronous Frequency Locking
|a>
|b> B+ B-
B-Clock B 
Bob B
Will Require Ensemble Interaction to Enhance Single Photon Coupling Rate

19. Summary on entanglement sources
Demonstrated an ultrabright source of polarization-entangled photons
Total output flux is entangled without spectral, spatial, or temporal filtering
novel configuration with bi-directional pumping and collinear propagation
795-nm center wavelength for coupling to trapped Rb
Demonstrated extended phase matching in PPKTP
100 nm phase-matching bandwidth for second harmonic generation
setting up to demonstrate coincident-frequency entanglement and full recovery of HOM dip in pulsed pumping

20. Ultrabright dual-pump downconversion source
An old idea…
Combine two identical sources
|HV + eif |VH 2
|Y =
PPKTP
Split pump I1 I2 S1 S2
…with a new twist
PPKTP source
Type-II collinear downconversion
One crystal with bi-directional pumping
Outputs are completely indistinguishable
Entanglement is independent of direction of emission and wavelength

21. Dual-pump SPDC experimental setup
|HV + eif |VH 2
|Y =
UV pump interferometer
controls the phase f:
singlet or triplet
quant-ph/

22. Characteristics of dual-pump SPDC
Almost independent of aperture size
High flux
Wavelength independent
main and left inset: IF = 3 nm filter

23. Quality of dual-pump polarization entanglement
Bell’s inequality measurements
q1=0
q1=45
0.76 mW pump power; 3-nm filter; aperture size = 3.1 mm
S = ± 0.006

24. SUMMARY OF PROGRESS
Observation and Analysis of BSO in an atomic beam under
multi-level excitation
Demonstration of a Single-Zone Atom-Interferometer
Demonstration of Launch and catch FORT, as precursor to single
trapped atoms
Construction of a Pair of Integrated Cavity-Fort for Remote Frequency
Locking
Demonstration of A Compact, High Flux Source for Polarization
Entangled Photon Pairs at 795 for Entangling Rb Memory Elements
Developed Model For How Entanglement Variation Can Be Used To
Infer Relativistic Effects And Correct For Them
Developed a Model for Using a Frequency Entangled Source For
Enhanced-Accuracy Timing Measurement
Developed Technique for Producing The Frequency Entangled Source
Built a Pair of Traps for Single Atom Plus Cavity for Freq Teleportation
Developed Technique for Freq Teleportation via
Single Atom Interferometry

25. MOST RELEVANT PUBLICATIONS/PREPRINTS
“Long Distance, Unconditional Teleportation of Atomic States Via Complete Bell State Measurements,” S. Lloyd, M.S. Shahriar,
J.H. Shapiro and P.R. Hemmer, Phys. Rev. Letts.87, (2001)
“Driver Phase Correlated Fluctuations in the Rotation of a Strongly Driven Quantum Bit," M.S. Shahriar, P. Pradhan, and
J. Morzinski, to appear in Phys. Rev. A.
“Physical Limitation to Quantum Clock Synchronization,” V. Giovanneti, L. Maccone, S. Lloyd, and M.S. Shahriar,
Phys. Rev. A 65, (2002)
“Wavelength Teleportation via Distant Quantum Entanglement Using the Bloch-Siegert Oscillation ” M.S. Shahriar,
P. Pradhan, V. Gopal, J. Morzinski, G. Cardoso, and G.S. Pati under review for Physical Review Letters
“In-Situ Observation of the Absolute Phase of a Microwave Field via Incoherent Fluorescence Detection
" G. Cardoso, P. Pradhan, and M.S. Shahriar, under review for Nature.
“Demonstration Of A Continuously Guided Atomic Interferometer Using A Single-Zone Optical Excitation,"
M.S. Shahriar, Y. Tan, M. Jheeta, J. Morzinksy, P.R. Hemmer and P. Pradhan, under review for Phys. Rev. Letts
“Continuously Guided Atomic Interferometry Using a Single-Zone Optical Excitation: Theoretical Analysis," M.S. Shahriar,
M. Jheeta, Y. Tan, P. Pradhan, and A. Gangat, under review for Physical Review A.
“Super Efficient Absorption Filter for Quantum Memory using Atomic Ensembles in a Vapor," A. Heifetz, A. Agarwal,
G. Cardoso, V. Gopal, P. Kumar, and M.S. Shahriar, to appear in Optics Communications
“Single-Photon, Single-Atom Interferoemetry for Entangling Macroscopic Rotors,“M. S. Shahriar, P. Pradhan, and R. Nair
to be submitted to Phys. Rev. Letts.
"Negligible Bloch-Siegert oscillation in an effective two level Lambda system : An advantageous platform for fast and precise
rotation of a qubit," P. Pradhan, G. Cardoso, J. Morzinski, and M.S. Shahriar , under review for J. Opt. Soc. Am. B.
R. Jozsa, D.S. Abrams, J.P. Dowling, and C.P. Williams, Phys. Rev. Letts. 85, 2010(2000)
U. Yurtsever and J.P. Dowling, “ Lorentz-invariant look at quantum clock synchronization protocols based on distributed
Entanglement,”quant-ph/
V. Giovannetti, S. Lloyd, L. Maccone, and F.N.C. Wong,"Clock Synchronization with Dispersion Cancellation,"
Phys. Rev. Letts. 87, (2001)
Robert M. Gingrich and Christoph Adami "Quantum Entanglement of Moving Bodies," Physical Review Letters, 89, (2002)
Attila J. Bergou, Robert M. Gingrich, and Christoph Adami "Entangled Light in Moving Frames," To appear in Phys Rev. A.
Ulvi Yurtsever "The Holographic Entropy Bound and Local Quantum Field Theory", http: //xx.lanl.gov/abs/gr-qc/
“Generation of ultrabright tunable polarization entanglementwithout spatial, spectral, or temporal constraints,” Marco Fiorentino,. Ga´etan Messin,
Christopher E.Kuklewicz, Franco N. C. Wong, and Jerey H. Shapiro, submitted to Phys. Rev. Letts