Post on 30-Aug-2018
Funded by Hosted by
Phase shift of a weak coherent beam
by a single atom
Thanks to
Chen Zilong
Florian Huber
Lee Jianwei
Timothy Liew
Valerio Scarani
Syed Abdullah Aljunid, Gleb Maslennikov, Tey Meng Khoon,
Brenda Chng, Christian Kurtsiefer
Brief Outline
• Motivation for the experiment
• Theoretical description
• Experiment and Results
Motivation
• Quantify interaction of a two-level atom with
light
• Strong interaction without a cavity.
Tey M.K. et al. Nature Physics 4, 924 - 927 (Dec 2008)
Scattering Ratio
in
scatscat
P
PR
Quantifying Interaction
Pscat
PscatPscat
Pscat
Pin
Scattering Ratio
Transmission
Phase shift
2
in
2
out EET
)arg( inout
EE
in
scatscat
P
PR
Quantifying Interaction
2
outE2
inE
Weak excitation, and on-resonant input light
Atom-Light Interaction
scatinout EEE
Weak excitation, and on-resonant input light
Atom-Light Interaction
i
iRE
221 scat
in(On axis)natural linewidth
detuning
scatinout EEE
Strong Interaction
G. Zumofen, et. al.,
Phys. Rev. Lett. 101, 180404 (2008)
M. K. Tey, et. al.
New J. Phys. 11 (2009) 043011
CClosed expression for focused
Gaussian beam
Strong Interaction
G. Zumofen, et. al.,
Phys. Rev. Lett. 101, 180404 (2008)
M. K. Tey, et. al.
New J. Phys. 11 (2009) 043011
CClosed expression for focused
Gaussian beam
0.84
2.30.16
Experimental Setup
Experimental Setup
Experimental Setup
Experimental Setup
Experimental Setup
Experimental Setup
Experimental Setup
Experimental Setup
probe2.5 cm
Phase Measurement
Mach-Zehnder interferometer.
dc
dc
PP
PParccos
1~~
2
~~
arccos'
''
''
dc
dc
II
IIc
d
Phase Measurement
Mach-Zehnder interferometer.
TPP
PP
dc
dc ''arccos'
dc
dc
PP
PParccos
'
1~~
2
~~
arccos'
''
''
dc
dc
II
IIc
d
1
)(2; ''
dc
dc
PP
PPT
Results
Transmission of
(93.9 ± 0.2)%
Max phase shift of
(0.9 ± 0.2) ° at~Γ/2
Rscat = 0.062 ± 0.003
= (8.6± 0.4)MHz
Theoretical
Transmission: 84%
max phase shift: 2.3°
22
2
scat22
2
in
2
out
4
214
R
E
ET
scatscat22
inout2
14arg)arg( iRR
EE
Conclusion
• Strong interaction of light with a single atom
can be observed by simple focusing.
• 0.9° phase shift of a weak coherent beam
observed together with 93.9% transmission.
Conclusion
• Strong interaction of light with a single atom
can be observed by simple focusing.
• 0.9° phase shift of a weak coherent beam
observed together with 93.9% transmission.
Thank You & The End
Antibunching in single atom fluorescence
Dipole trap laser wavelength: 980 nm
trapping
potential