Motivation - 学校法人東邦大学HFS Specific mass shift Electron density Electronic...
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Stark Effect Motivation Search for permanent electric dipole moments of atoms (Fr) Parity nonconservation (Cs forbiden transition) Tests of Standard Model Stark Effect Interaction between electric field and atoms Spectroscopic data of polarizability Particularly for alkali atoms needed
Transcript of Motivation - 学校法人東邦大学HFS Specific mass shift Electron density Electronic...
Stark Effect Motivation
Search for permanent electric dipole moments of atoms (Fr) Parity nonconservation (Cs forbiden transition)
Tests of Standard Model
Stark EffectInteraction between electric field and atoms
Spectroscopic data of polarizabilityParticularly for alkali atoms
needed
MotivationAlkali atoms: simple atomic structure Precise theoretical calculation possible
Systematic studyRelativistic effectCore contribution
Precise polarizability data : needed For tests of calculation
MotivationStark effect: strong electric field
Difficult to produce strong field
Less study for Stark effectEven for alkali atoms
Toho university:Systematic study of Stark effect for alkali atoms
Li, K, Rb, CsBy high-resolution spectroscopy
TheoryStark Effect
EpHrr
⋅−= ∑−=j
jrep rr P: electric dipole moment
E: electric field
( )mFJ ,,γ
αs : scalar polarizabilityαt : tensor polarizability
( ) 2
21 EW ts γαα +−=Δ
2EW ∝Δ
←2nd-order perturbation
Energy Shift
∑ −=Δ
j ji
ji
EE
HW
2φφ
Wave function
TheoryStark shift < HFS
( ) ( )[ ] ( ) ( ) ( )[ ]( )( ) ( ) ( )12122232
1141313,,2
−−++++−−+−
=JJFFFF
JJFFXXFFmmFJ Fγ
( ) ( ) ( )111 +−+++= IIJJFFX
J=1/2 αt =0
J: electronic angular momentF: total angular moment of atomI: nuclear spinmF : magnetic quantum number
J≧1 αt , αs
shift
Shift+split
(J,F)(J,F’)
(J,F’,|mF |)(J,F)
Experimental Setup
Atomic Beam SourceBaffle Baffle
Laser BeamPhotomultiplier
Electrode2～3mm
AtomicBeam
Lens
Mirror
SphericalMirror
Filter
Wavemeter
Lens
MirrorBeamSplitter
BeamSplitter
Semiconductor Laser
Photodiode
Fabry-PerotInterferometer
Φ6mm 1.5m
Strong Field
High Resolution
Separated Electrode System
2.0㎜Atomic beam
Laser
・Two Electrodes: Separated
Less electric dischargeStronger field
・Hard to measure distance
Compact Electrode System
distance between electrodes: stable
Stable & uniform field
Independent of flangeEasy to set
Atomic beam
Laser
Internal Focus System
Interaction region～<1mm
Transitions Measured for Rb
D1 D2
5s
5p 2P1/2
2P3/2
2S1/2
5s 2S1/2
→5p 2P1/2 (794.8nm)
D1
5s 2S1/2
→5p 2P3/2 (780.0nm)
D2
Rel
ativ
e In
tens
ity [a
rb.u
nits
]
Relative Frequency [GHz]0.0 2.0 4.0 6.0 8.0
5s
5p
2P1/2
2S1/2
3
2
3
2
F
3 4
5 6
85Rb I＝5/2
794.8 nm
5s
5p
2P1/2
2S1/2
2
1
2
1
F
1 2
7 8
87Rb I＝3/2
794.8 nm
1
34 6
5
782
15MHｚ
HFS Spectrum of Rb D1 Transition
0 0.3 0.6 0.9 1.2 1.5 1.8
0kV/cm
81.5kV/cm
Relative Frequency [GHz]
Rel
ativ
e In
tens
ity [a
rb.u
nits
]
5s
5p
2P1/2
2S1/2
794.8nm
F
3
2
3
2
3 4
5 6
8 5 R b I ＝ 5 / 2
3 4
Stark Spectrum of Rb D1 transition
0
1 0 0
2 0 0
3 0 0
4 0 0
5 0 0
0 1 0 0 0 2 0 0 0 3 0 0 0 4 0 0 0 5 0 0 0 6 0 0 0 7 0 0 0
E2 〔（kV/cm）2〕
-Sta
rk S
hift
〔M
Hz〕
( ) ( )[ ] 22/1
22/1
2
21 ESPW ss αα −−=Δ
Dependence of Stark shift on electric field D1 transition
HFS Spectrum of Rb D2 Transition R
elat
ive
Inte
nsity
[arb
.uni
ts]
Relative Frequency [GHz]2.01.0 3.0 4.00.0 5.0
5p 2P3/2
85Rb I=5/2
5s 2S1/2
780.0nm
2
2
1
3
F
3
1
2
5
6
18MHz
4
3
5p 2P3/2
87Rb I=3/2
5s 2S1/2
780.0nm
F
2
3
23
1
4
6.0
89
4 1210
711
85Rb
87Rb
87Rb
85Rb
321654
987 10 11 12
0.0kV/cm
32.3kV/cm
64.5kV/cm
80.6kV/cm
Relative Frequency [GHz]
Rel
ativ
e In
tens
ity [a
rb.u
nits
]
5s
5p
2P3/2
2S1/2
2
1
2
1
F
780.0nm
3
0
mF
32
10
10
3
1
2
3
0.2 0.4 1.21.00.80.6 1.40
Stark Spectrum of Rb D2 Transition
E2 〔（kV/cm）2〕
-Sta
rk S
hift
〔M
Hz〕
0
100
200
300
400
500
600
0 1000 2000 3000 4000 5000 6000 7000
８７Rb５ｓ 2S1/2
(F=2)→
５p 2P3/2
(F=3,|mF
|)
|mF
|=0
|mF
|=1
|mF
|=2
|mF
|=3
80.6kV/cm△
◇
Dependence of Stark Shift on Electric Field D2 Transition
( ) ( ) ( )[ ] 22/1
22/3
22/3
2
21 ESPPW sts αγαα −+−=Δ
110.6±0.9
146±32
-54.0±3.1
-40±6
Scalar & Tensor Polarizability Rb D1, D2 Transition
α0 (2P3/2 ) – α0 (2S1/2 ) αt (2P3/2 )
⎥⎥⎦
⎤
⎢⎢⎣
⎡⎟⎠⎞
⎜⎝⎛
2
cmkVkHz
⎥⎥⎦
⎤
⎢⎢⎣
⎡⎟⎠⎞
⎜⎝⎛
2
cmkVkHz
a: Richard Marrus, Douglas Mccolm and Joseph Yellen : Phys. Rev. 147, 55 (1966).b: Arthur Salop, Edword Pollack and Benjamin Bederson: Phys. Rev. 124, 1431 (1961).
aa, b
This Work
Reference
αｓ
(2P1/2 ) – αｓ
(2S1/2 )
137.0±0.6
121±18a
D 1 D 2
⎥⎥⎦
⎤
⎢⎢⎣
⎡⎟⎠⎞
⎜⎝⎛
2
cmkVkHz
Summary
1. High-resolution UV Laser SpectroscopyHFSSpecific mass shiftElectron densityElectronic configuration
2. Stark EffectElectrode systemRb D1 and D2Stark shift and splittingScalar and tensor polarizability
