quantum coherent control with non-classical light
DESCRIPTION
Quantum Coherent Control with Non-classical Light. Department of Physics of Complex Systems The Weizmann Institute of Science Rehovot, Israel. Yaron Bromberg, Barak Dayan, Avi Pe’er, Itai Afek, Yaron Silberberg. The Ultrafast Optics Group. THG images of biological specimen. - PowerPoint PPT PresentationTRANSCRIPT
Quantum Coherent ControlQuantum Coherent Controlwith Non-classical Lightwith Non-classical Light
Department of Physics of Complex SystemsDepartment of Physics of Complex SystemsThe Weizmann Institute of ScienceThe Weizmann Institute of Science
Rehovot, IsraelRehovot, Israel
Yaron Bromberg, Barak Dayan, Avi Pe’er, Itai Afek,
Yaron Silberberg
The Ultrafast Optics GroupThe Ultrafast Optics Group
10 fs pulses @ 800 nm ~130 nm FWHM
THG images of biological specimenTHG images of biological specimenFemtosecond Pulse ShapingFemtosecond Pulse Shaping
SLM
Phase, amplitude and polarization synthesizer
Spectral plane
QCC with Non-classical LightQCC with Non-classical Light
Can we shape a single photon?
… what does it really mean?
… and what is it good for?
Spontaneous Parametric Down-conversionSpontaneous Parametric Down-conversion
a pump photon is spontaneously converted into two lower frequency photons
ps
ienergy
conservation
momentum conservation
(phase matching)pk
sk
ik
non linear crystal
pumpsignal
idler
Continuous Broadband Down-conversion:Continuous Broadband Down-conversion:Time-Energy Entangled PhotonsTime-Energy Entangled Photons
5p MHz
THznm 1030
PUMP (cw)
)2(
SIGNAL (cw)
IDLER (cw)
, 0s i s s i it t E t E t
The two-photon wavefunction
1 0.2p s
is tt 21
is tt 1 100 fs
2/2/
1,1)(0)1(pp
gd
Gate
• The time DIFFERENCE between the photons behaves as a fs pulse
Time-Energy Entangled PhotonsTime-Energy Entangled Photons
non linear crystal
pump )cw(
signal )cw(
idler )cw(
… so lets shape the two-photon correlation function !
• But electronics limits temporal resolution to ~ns
Shaper
1. Hong-Ou-Mandel Interference
2. Instantaneous nonlinear interaction between photons
How can we get fs resolution?How can we get fs resolution?
c
~
“Measurement of Subpicosecond Time Intervals between Two Photons by Interference”
C.K. Hong, Z.Y. Ou and L. Mandel, PRL 59 (1987)
IDLER
SIGNAL
PUMP )2(
d
Two-Photon Coincidence Interference :Two-Photon Coincidence Interference : Hong-Ou-Mandel DipHong-Ou-Mandel Dip
Shaper
HOM in polarizationHOM in polarization
Pump364 nm
Computer
SLM
FourierPlane
PBS
V
1
2H
)(
V
φ
2 type-I crystals generatepolarization entanglementand broad spectrum
isis
isis
XYYX
VVHH
2
12
1
H
XV
Y
is
i
isVVeHH
2
1
A. V. Burlakov et. al. , PRA 64, (2001)
Experimental SetupExperimental Setup
Pump364 nm
Computer
crystalsSLM
FourierPlane
PBS
V
1
2H
)(
Phase-and-polarization SLMControls independently the ±45° axes (X,Y)
Experimental ResultsExperimental Results
B. Dayan, Y. Bromberg, I. Afek and Y. Silberberg, in preparation.
1. Hong-Ou-Mandel Interference
2. nonlinear interaction between photons (instantaneous)
How can we get fs resolution?How can we get fs resolution?
Coincidence detection through Coincidence detection through Sum-Frequency Generation (SFG)Sum-Frequency Generation (SFG)
CW PUMP
)2(
SIGNAL )CW(
IDLER )CW(
)2(
910~ 1510~ s 1410 stypical flux SFG efficiency SFG signal
Delay
Delay
13 -1max 10 s 2 !!W
1
1
1
A photon-pair per time-bin
The photon-pair arrives within 1/
How many ‘single photons’ can arrive in one second ?How many ‘single photons’ can arrive in one second ?
(How high can ‘low light levels’ be ?)(How high can ‘low light levels’ be ?)
(n=1 photon per mode)
Quantum mechanical analysis of SFG
0
22
0
22
0nnnR SFGSFG
0n - photons per mode
2I Ientangled photons
1995: Kimble’s groupmeasures a slope of 1.3at low photon numbers
Down-convertingcrystal
SFGcrystal
pump 532nm5W
IR detector
SPCM
Beam dump
Dispersioncompensation
Computer
SFG with Entangled PhotonsSFG with Entangled Photons
PP-KTPPP-KTP
SFG 532nm~40,000 s-1
0
Intensity Dependence of SFG with Entangled Photons
0n 02
0 nn
"Nonlinear Interactions with an Ultrahigh Flux of Broadband Entangled Photons",
B. Dayan, A. Pe’er, A.A. Friesem and Y. Silberberg, Phys. Rev. Lett. 94, 043602 (2005)
Down-convertingcrystal
up-convertingcrystal
Pump 532nm
IR detector
SPCM
Beam dump
Computer
Shaping of Entangeled PhotonsShaping of Entangeled Photons
Fourierplane
SLM )(
"Temporal Shaping of Entangled Photons",A. Pe’er, B. Dayan, A.A. Friesem and Y. Silberberg, Phys. Rev. Lett. 94, 073601 (2005)
Temporal shaping of the two-photon wavefunctionTemporal shaping of the two-photon wavefunction
We have seenWe have seen……
• Control of HOM interference
• Shaping of two-photon correlation functions
• Linear SFG for low light levels
• SFG as coincidence detection
Pulse shaping offers a new tool for quantum information
Pulse Shaping
Nonlinear interactions