electromagnetic cavity tests of lorentz invariance on...
TRANSCRIPT
Electromagnetic cavity tests of Lorentz invariance on Earth and in space
46th Recontres de Moriond, La Thuile / Italy
Prof. Achim Peters, Ph.D.
March 20-27, 2011
Michelson-Morley Experiment using optical resonators
Optische
Metrologie
Michelson-Morley experiments: History
Classical Michelson(-Morley) experiment
Berlin
Potsdam
Berlin / Potsdam: 1881
Michelson-Morley Experiment
Michelson (1881, Potsdam)Michelson & Morley (1887, Cleveland)
rotate
source
mirror
mirrorbeam splitter
observer
Modern Setup Brillet & Hall (1979, Boulder)
rotate
opticalresonator
beatmeasurement
First generation experiment (Konstanz)
• Cryogenic sapphire optical resonators (CORE)
• Operated at LHe temperature (4.2 K)
• Solely relied on Earth’s rotation
• ~ one Year of data
= (0.73 ±
0.48) Hzc/c = (2.6 ±
1.7) ·
10-15
Second generation experiment (Berlin)
• Used fused silica resonators (BK7 mirrors)
• Operated at room temperature
• Used precision air-bearing turntable
• ~ 1 year of data (with large gaps)
= (0.070 ±
0.076) Hzc/c = (2.5 ±
2.7) ·
10-16
Third generation experiment (Berlin)
• Fused silica mono-block resonators (Finesse ~ 400 000)
• Operated at room temperature
• Optimized chamber (thermal + mechanical)
• Precision air-bearing turntable
• ~ 1 year of data (with large gaps)
δν
= (0.002 ±
0.003) Hzc/c = (6.2 ±
12.3) ·
10-18
Data analysis
Data taken over more than one year (with gaps):
~ 1900 rotations per day at Trot = 45 seconds
~ 700 000 rotations total
employ multi-step data analysis procedure …
Data analysis
SME Lorentz-Invariance violation parameters (x 10-17)
Data taken over more than one year yield:
•
Limits are an order of magnitude more stringent as compared to the previous best laboratory measurements
• All parameters consistent with zero within three sigma
Herrmann, Senger et al. Phys. Rev. D80, 105011, (2009)
Current limitations ?
Thermal Noise in Optical Cavities
Future experiments
Optische
Metrologie
Beating the thermal noise …
Options:
back to the future … cryogenic resonators
avoid thermal noise regime rapid rotation (10 Hz ?)
massive parallelism thousands of resonators …
Rotating CryostatPVLAS vacuum birefringence experiment
Beating the thermal noise …
Options:
back to the future … cryogenic resonators
avoid thermal noise regime rapid rotation (10 Hz ?)
massive parallelism thousands of resonators …
Rotating CryostatPVLAS vacuum birefringence experiment
Big turntable(Kugler
GmbH) Large volume cryostat
Beating the thermal noise …
Old CORE specifications:• Sapphire• Mirror spacing 3 cm• Finesse 100 000• Linewidth
50 kHz
•
Longer COREs
with higher finesse reasonable improvement in frequency stability of up to two orders of magnitude
2010
8sec22sec10
107
16
•
Rel. freq. deviation of ~10-16
at half the rotation rate (22 s)
one year of
measurement yields an standard error of:
Additional measurement options …
Optische
Metrologie
Joining forces …
Joining forces …
Large volume cryostat
Optical resonators (linear)
Microwave resonators(whispering gallery)
But first …
HU Berlin Experiment UWA Perth Experiment
But first …
HU Berlin Experiment UWA Perth Experiment
Additional precursor experiments
Optical Metrology
A slightly modified MM-Experiment …
Light propagating inside matter …
Monolithic Sapphire Resonator?
Multi resonator experiment
Multi resonator experimentMonolithic sapphire resonator cooled down to 4K !
300 K
4 K
• Flawed coatings
Finesse of only 10 000
Very bad impedance matching (t ~ 10-6)
• High thermal sensitivity at 293K
Experiments at 4K essential …
Monolithic Sapphire Resonator
δν
= (0.022 ±
0.020) Hzc/c = (0.8 ±
0.7) ·
10-16
Multi resonator experiment
Also: More SME obtainable than in previous experiments: 15 instead of 8 …
Additional technology development …
Optische
Metrologie
Beating the thermal noise – going further …
CORE (2003)FS (2007)
ULE (1999)ULE (2011)
Beating the thermal noise crystalline mirrors !
Collaboration:Prof. Markus AspelmeyerDr. Garret Cole
Dr. Markus Weyers
Beating the thermal noise crystalline mirrors !
Collaboration:Prof. Markus AspelmeyerDr. Garret Cole
Dr. Markus Weyers
First results with MOVPE grown DBRs:(not
yet optimized for low optical loss)
• Q > 9 ×
104
at 2.4 MHz at 20 KΦ
< 1.1 ×
10-5
(still not limited by material, but by geometry)
• R > 99.98 %
Finesse > 16000G.
Cole, I.
Wilson-Rae, M.
Vanner, S.
Groblacher, J.
Pohl, M.
Zorn, M.
Weyers, A.
Peters, and M.
Aspelmeyer, “Megahertz monocrystalline
optomechanical
resonators with minimal dissipation,”
jan. 2010, pp. 847 –850.
Beating the thermal noise crystalline mirrors !
CORE (2003)FS (2007)
ULE (1999)ULE (2011)
- in Space -Perspectives
Satellite-based tests of Special and General Relativity
Germany
University Düsseldorf
ZARM, University Bremen
Humboldt-University
Berlin
Italy
University Lecce
University Bari France
ONERA
Observatoire
Cote Azur UK
RAL
OPTIS
Submitted ProposalExplorer 2011 Science Mission of Opportunity
Folie 41STAR meeting Bremen 2010 > Achim Peters > WG2: Iodine Standard > December 1st 2010
Iodine standard @ HUB
10-3 10-2 10-1 100 101 102 103 10410-16
10-15
10-14
10-13
10-12
Averaging time [s]
Alla
n D
evia
tion y(
)
Hum
bold
t-Uni
vers
ität z
u B
erlin
, AG
Opt
isch
e M
etro
logi
e
estimated stability 508 nm
extrapolated stability 532 nm
HU-Berlin Iodine (vs. ULE)HU-Berlin Iodine (vs. ULE)Jun Ye et al. (1999)Jun Zang et al. (2007)
Thank you
Optische
Metrologie