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

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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

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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 …

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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 …

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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

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