QUEST - Centre for Quantum Engineering and Space-Time Research
Multi-resonant spinor dynamics in a Bose-Einstein
condensate
Jan Peise
B. Lücke, M.Scherer, O. Topic,W. Ertmer, C. KlemptInstitute of Quantum Optics, Leibniz Universität Hannover
G. Gebreyesus, F. Deuretzbacher, L. SantosInstitute of Theoretical Physics , Leibniz Universität Hannover
J. ArltQUANTOP, Institut for Fysik og Astronomi, Aarhus Universitet, Denmark
QUEST - Centre for Quantum Engineering and Space-Time Research
Light AtomsOptics Atom optics
Coherent optics Atom optics withBose-Einstein condensates
Non-classical optics
Non-classical atom optics
Light and atoms for interferometry
2
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Parametric amplificationvs.
spin dynamics
Optical parametric amplification
• Coherent pump• Non-linear crystal• Signal and idler beam
Spinor Bose-Einstein condensate
• 87Rb BEC in mF=0
• Spin dynamics
• Atoms in mF=±1
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Introduction
Experimental setup
Spin dynamic resonances
Spin dynamics via microwave dressing
Content
QUEST - Centre for Quantum Engineering and Space-Time Research
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87Rb atoms in a dipole trap
87Rb
F=2
mF= -2 -1 0 +1 +2
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Absorption detection
mF=-1
mF=0
mF=1
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Introduction
Experimental setup
Spin dynamic resonances
Spin dynamics via microwave dressing
Content
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Simplified model for spin dynamics
DE0; 1
DE0; -1
Effective potential for mF=+/-1 atoms
Multiresonant spinor dynamics in a Bose-Einstein condensate,Klempt et al., Phys. Rev. Lett. 103, 195302 (2009)
1E
2E
3E
nE
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Spin dynamic resonances in a cylindrical trap
2
, ),( rln
Effective potentialwith cylindrical symmetry
magnetic field
pop
ulat
ion
in m
F=
±1
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magnetic field
pop
ulat
ion
in m
F=
±1
Spatial modes populated by spin dynamics
magnetic field
Spontaneous Breaking of Spatial and Spin Symmetry in Spinor CondensatesScherer, et.al, Phys. Rev. Lett.,105, 135302 (2010)
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Introduction
Experimental setup
Spin dynamic resonances
Spin dynamics via microwave dressing
Content
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Instability rates
Instability rate
Maximal for
2eff
2,, )( qE lnln
]Im[ ,lnE
0, qlntE lnetn ]Im[ 4
1mF,)(
Inst
abi
lity
rate
Im
[E]
2~]Hz[ Bq
10eff Un
In F=1:
10
resonance 10
1011
1
ttUU F
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Spin dynamics in F=1
F=2U1>0
F=1U1<0
Zeeman splitting in F=1
DE0; 1
DE0; -1
0: 1,01,0 EEq
Fre
qu
en
cyMagnetic field
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Dressed states
Bare states
1
01
0
1
2
1
ng
ne
n
n
Reminder
0
0
2
1)1(2/
2/2
1
n
nH
Ω resonant Rabi frequencyω laser frequencyω0 atomic frequency
Hamiltonian
Dressed states
)( 0
AC Stark shift
0
0
2
1)1(0
02
1
n
nH
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Microwave dressing
Res
onan
ce fr
eque
ncy-
6 8
34 6
83 H
z
F=1
F=2
mF=-2 mF=-1 mF=0 mF=1 mF=2
Fixed magnetic fieldNo spin dynamics
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Spin dynamics via microwave dressing
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Thank you for your attention.