harald lück for the geo team
DESCRIPTION
The GEO-HF Project. Harald Lück for the GEO team. ILIAS Meeting Palma, October 2005. What is GEO-HF ?. A research and upgrade program instead of the name of a new detector sequential upgrades of GEO600 (similar to LIGO+ / VIRGO+ ) prototype research to prepare these upgrades - PowerPoint PPT PresentationTRANSCRIPT
Harald LückHarald Lückfor the GEO teamfor the GEO team
ILIAS Meeting
Palma, October 2005
What is GEO-HF ?What is GEO-HF ?
A research and upgrade programA research and upgrade program instead of the instead of the name of a new detector name of a new detector
sequential upgradessequential upgrades of GEO600 (similar to of GEO600 (similar to LIGO+ / VIRGO+ )LIGO+ / VIRGO+ )
prototype researchprototype research to prepare these upgrades to prepare these upgrades support transit of support transit of 3rd generation3rd generation Lab research to Lab research to
detector subsystems or detector configuration detector subsystems or detector configuration
12W Laser
modecleaner
interferometer with „dual recycling“
detector
Optical LayoutOptical Layout
101
102
103
10-24
10-23
10-22
10-21
10-20
10-19
10-18
Freq. [Hz]
ASD
[h/
Hz]
GEO600 Theoretical Noise Budget
v2.0
SeismicSuspension TNSubstrate TNCoating TNThermorefractiveShot 200HzTotal
GEO600 Noise Sources GEO600 Noise Sources (Design values)(Design values)
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Freq. [Hz]
ASD
[h/
Hz]
GEO600 Theoretical Noise Budget
v2.0
SeismicSuspension TNSubstrate TNCoating TNThermorefractiveShot 1 kHzTotal
GEO600 Noise Sources GEO600 Noise Sources (Design values)(Design values)
GEO HF - MotivationGEO HF - Motivation Provide scientifically interesting data with the GEO Provide scientifically interesting data with the GEO
instrument until 2014instrument until 2014– optimized at low frequencies for network analysis oroptimized at low frequencies for network analysis or– optimized for high frequency sources optimized for high frequency sources
Perform developments and tests towards third Perform developments and tests towards third generation detectors generation detectors – technologies, materials and optical schemes technologies, materials and optical schemes
Maintain capability to do high-fidelity Maintain capability to do high-fidelity measurementsmeasurements– Discover and analyze additional noise sources Discover and analyze additional noise sources – keep team of experts in GEO collaborationkeep team of experts in GEO collaboration
→ upgrade GEO600 and work on prototypes
Shot NoiseShot Noise
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10-21
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Freq. [Hz]
ASD
[h/
Hz]
GEO Theoretical Noise Budget
SeismicCoating TNThermorefractiveShot 1 kHzShot 200HzShot 500Hz
High Frequency SourcesHigh Frequency Sources
Possible way forward for Possible way forward for ‘GEO-HF’‘GEO-HF’
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103
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10-23
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Freq. [Hz]
ASD
[h/
Hz]
GEO Theoretical Noise Budget
SeismicCoating TNThermorefractiveShot 1 kHz
improvements without improvements without changing mirrorschanging mirrors– increase circulating powerincrease circulating power– improve thermal improve thermal
compensation schemecompensation scheme– optimize signal recycling optimize signal recycling
bandwidthbandwidth use squeezed light to use squeezed light to
reduce shot noisereduce shot noise change main mirrorschange main mirrors
– reduce coating thermal reduce coating thermal noise if possiblenoise if possible
– further increase circulating further increase circulating power and / or reduce power and / or reduce signal recycling bandwidthsignal recycling bandwidth
Laser
modecleaner
interferometer with „dual recycling“
detector
ChangesChanges
increase laser power
40W / 200W
Nd:YAG 200W Laser SystemNd:YAG 200W Laser System
0.8W12W
200W
Injection-Locked Single Frequency PowerInjection-Locked Single Frequency Power
P = 195 W
continuous single-frequency
operation >8h
00:00 00:10 00:20 00:30 00:400
50
100
150
200
Ou
tpu
t P
ow
er
[W]
Time [hh:mm]
400 500 600 700 800 900 1000 1100 12000
50
100
150
200
250
300
Slope: 30 %
Out
put P
ower
[W]
Pump Power [W]
930 940 950 960 970205
210
215
220
225
230
213 W; M2 =1,14
215 W; M2 =1,2
218 W; M2 =1,3
225 W; M2 =1,45
Out
put P
ower
[W]
Pump Power [W]
4 Rod Nd:YVO4 Rod Nd:YVO44
AmplifierAmplifier39W output power11W seed / 115W pump
GEO 600 style
11W seed laser
2/8/2 mm Nd:YVO4 rod
Laser
modecleaner
interferometer with „dual recycling“
detector
ChangesChanges
reduce Finesse of MC to keep peak intensity
constant
•mid-arm pumping
•new gate valves
Laser
modecleaner
interferometer with „dual recycling“
detector
ChangesChanges
•(reduce absorption)
•thermal compensation
Faraday Rotator
Squeezed state
Squeezed lightSqueezed light
Signal-recycling mirror
Power-Recycling mirror
Laser
Photo diode
600 m
600 m
Rotated Squeezing EllipseRotated Squeezing Ellipse
Table Top SetupTable Top Setup
Sqeezing Enhanced Sqeezing Enhanced Signal/Noise Signal/Noise
Laser
modecleaner
interferometer with „dual recycling“
detector
Optional ChangesOptional Changes
replace main mirrors
Further GEO-HF Further GEO-HF optional changesoptional changes
based on thermal noise based on thermal noise considerations we consider considerations we consider replacing the end mirrors with replacing the end mirrors with new mirrorsnew mirrors
better coatingsbetter coatings (mechanical and (mechanical and optical losses) if availableoptical losses) if available
possibly switch to possibly switch to silicon/ silicon/ sapphiresapphire if thermal noise if thermal noise performance is better than in performance is better than in fused silicafused silica
Coated fused silica mirror for GEO600
~18cm diameter
Thermal Noise for GEO Main Thermal Noise for GEO Main OpticsOptics
102
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Frequency [Hz]
h [H
z-1/2
]
GEO-HF noise levels based on best possible coating losses
full coating, silicadoped coating, silicaaperiodic coating, silicasilica substratethermorefractive BS
Ongoing lab work on Ongoing lab work on coatingscoatings
Considerable work in LIGO Scientific Collaboration Considerable work in LIGO Scientific Collaboration and elsewhere on studies of coating lossand elsewhere on studies of coating loss
Results suggest:Results suggest:– TaTa22OO55 is dominant source of coating dissipation is dominant source of coating dissipation – doping Tadoping Ta22OO55 with TiO with TiO2 2 can reduce dissipation by ~factor 2can reduce dissipation by ~factor 2
Further, studies by Pinto et al suggest by using multi-Further, studies by Pinto et al suggest by using multi-layers of ‘non-standard’ periodicity fraction of lossy layers of ‘non-standard’ periodicity fraction of lossy high index material may be reduced?high index material may be reduced?
SiliconSilicon
Strong interest in cryogenic silicon for use in ‘3Strong interest in cryogenic silicon for use in ‘3 rdrd generation detectors’generation detectors’
Laboratory studies ongoing on:
fabrication of, and dissipation in, silicon suspension elements
intrinsic dissipation in bulk silicon
fabrication and dissipation of monolithic silicon pendulums
e.g. GEO-HF, EGO
Silicon suspension technology.
future detectors
Thermal noise optionsThermal noise options
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Frequency [Hz]
h [H
z-1/2
]
full coating, silicadoped coating, silicaaperiodic coating, silicasilica substrateaperiodic coating, sapphiresapphire substrateaperiodic coating, siliconsilicon substrate
Prototype Work within Prototype Work within GEO-HFGEO-HF
Glasgow Glasgow (in operation):(in operation): – Advanced Configuration PrototypeAdvanced Configuration Prototype– Cryogenic Materials Test SystemCryogenic Materials Test System
Hannover Hannover (planned):(planned):– test subsystem before installation in GEOtest subsystem before installation in GEO
active seismic isolation system active seismic isolation system digital control digital control fast mirror installation tools and techniquesfast mirror installation tools and techniques
– test 3rd Generation techniques and configurationstest 3rd Generation techniques and configurations
GEO-HF SummaryGEO-HF Summary
We plan to We plan to operate a flexible GW detectoroperate a flexible GW detector in a worldwide in a worldwide network until advanced IFOs come online.network until advanced IFOs come online.
Sequential upgradesSequential upgrades to improve high frequency sensitivity to improve high frequency sensitivity will be made.will be made.– higher circulating powerhigher circulating power– lower coating thermal noise ( ? )lower coating thermal noise ( ? )– squeezed light injectionsqueezed light injection
GEO collaboration will GEO collaboration will operate prototypesoperate prototypes to prepare to prepare these upgrades and these upgrades and
to support the transit of to support the transit of 3rd generation3rd generation Lab research to the Lab research to the detector subsystems or detector configuration level.detector subsystems or detector configuration level.
Timeline: starting upgrading after extended data taking Timeline: starting upgrading after extended data taking 2007/20082007/2008
Proposal for ~3.5 M€ approved by MPGProposal for ~3.5 M€ approved by MPG
0.0E+00
2.0E-08
4.0E-08
6.0E-08
8.0E-08
1.0E-07
1.2E-07
1.4E-07
30 35 40 45 50 55 60
Frequency (kHz)
Lo
ss
[111]
[100]
Results for silicon at room temperatureResults for silicon at room temperature
Lowest loss obtained so far = Lowest loss obtained so far = (9.6 +/- 0.3) x 10-9
Comparable with the lowest loss factors measured at room Comparable with the lowest loss factors measured at room temperaturetemperature(consistent with results by Mitrofanov et al from earlier times)(consistent with results by Mitrofanov et al from earlier times)
(Cryogenic measurements in preparation)(Cryogenic measurements in preparation)
The doped [111] sample typically showed lower dissipation, though whether this was due to the crystalline orientation of the sample, the dopant, or some other reason, is as yet unknown.
Measured loss factors for two samples of bulk silicon
Bandwidth Finesse of the SR cavity Reflektivity of MSR
Signalrecycling-Etalon (r=150mm, d=75mm)
Reflectivity is controlled by temperature
Controlling the SR bandwidthControlling the SR bandwidth
Heater
Diffraction GratingsDiffraction Gratings
1st order Littrow
2nd order Littrow
All-Reflected CavitiesAll-Reflected Cavities
University of Jena
Littrow order 1st 2nd
Finesse 15801580 400400
diff. efficiency 99.62%99.62% 0.58%0.58%
loss 0.2%0.2% 0.4%0.4%
Title: The GEO-HF Project Title: The GEO-HF Project
Abstract: The GEO 600 gravitational wave detector uses advanced Abstract: The GEO 600 gravitational wave detector uses advanced technologies like signal recycling and monolithic fused-silica suspensions to technologies like signal recycling and monolithic fused-silica suspensions to achieve a sensitivity close to the km scale LIGO and VIRGO detectors. As achieve a sensitivity close to the km scale LIGO and VIRGO detectors. As soon as the design sensitivity of GEO600 is reached the detector will be soon as the design sensitivity of GEO600 is reached the detector will be operated as part of the worldwide network to acquire data of scientific interest. operated as part of the worldwide network to acquire data of scientific interest. The limited infrastructure at the GEO site does not allow for a major upgrade of The limited infrastructure at the GEO site does not allow for a major upgrade of the detector. Hence the GEO collaboration decided to improve the sensitivity of the detector. Hence the GEO collaboration decided to improve the sensitivity of the GEO detector by small sequential upgrades some of which will be tested in the GEO detector by small sequential upgrades some of which will be tested in prototypes first. The development, test and installation of these upgrades are prototypes first. The development, test and installation of these upgrades are named "The GEO-HF Project" and this contribution will give a status report on named "The GEO-HF Project" and this contribution will give a status report on this project. this project.
contentscontents GEO600GEO600
– descriptiondescription– current sensitivitycurrent sensitivity– limitslimits
GEO HF DetectorGEO HF Detector– motivationmotivation– sourcessources– ways forwardways forward
increase circulating power and power handling capabilityincrease circulating power and power handling capability change optics if coating technology allows for lower coating thermal noisechange optics if coating technology allows for lower coating thermal noise use squeezed lightuse squeezed light
GEO HF PrototypesGEO HF Prototypes– test subsystems / optical layout before installation test subsystems / optical layout before installation – test installation procedures for fast installation at site test installation procedures for fast installation at site – allow for high displacement sensitive measurements allow for high displacement sensitive measurements – test and develop third generation materials, optical readout schemes, control test and develop third generation materials, optical readout schemes, control
schemesschemes
Improvements to GEO Improvements to GEO sensitivity possible by sensitivity possible by
changing to silicon mirrors? – changing to silicon mirrors? – possible option.possible option.
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10-23
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Frequency [Hz]
h [/
Hz]
substrate, fp, cavities silicon, silica bscavitiesbsdoped coating, totalcoating, cavitiescoating, bstotal (fp substrate + fp coating)thermorefractive
Improvements to GEO Improvements to GEO sensitivity possible by sensitivity possible by
changing to silicon mirrors? – changing to silicon mirrors? – possible option.possible option.
101
102
103
104
10-24
10-23
10-22
Frequency [Hz]
h [/
Hz]
substrate, fp, cavities silicon, silica bscavitiesbsdoped coating, totalcoating, cavitiescoating, bstotal (fp substrate + fp coating)
102
103
104
10-24
10-23
10-22
10-21
Frequency [Hz]
h [H
z-1/2
]GEO-HF noise levels based on best possible coating losses
full coating, silicadoped coating, silicaaperiodic coating, silicasilica substrateaperiodic coating, sapphiresapphire substrateaperiodic coating, siliconsilicon substrate
102
103
104
10-24
10-23
10-22
Frequency [Hz]
h [H
z-1/2
]GEO-HF noise levels based on best possible coating losses
full coating, silicadoped coating, silicaaperiodic coating, silicasilica substrateaperiodic coating, sapphiresapphire substrateaperiodic coating, siliconsilicon substrate
Current estimate of thermal Current estimate of thermal noise limited sensitivity of noise limited sensitivity of
GEO GEO
Uses:Uses:– Substrate loss of 1 x 10Substrate loss of 1 x 10-7 -7 (Suprasil mirrors)(Suprasil mirrors)– Current SiOCurrent SiO22/Ta/Ta22OO55 coatings coatings
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10410
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Frequency [Hz]
h [
/H
z]substrate, loss = 1e-7standard coatingTotal (coating + substrate)
Phase squeezing
Squeezing at 45°
Phase squeezing
Amplitude squeezing
Phase squeezing
Squeezing at 45° Squeezing at -45°
Amplitude squeezing
Phase squeezing
Squeezing at 45°
Frequency dependent
squeezing, (single filter cavity)
Squeezing vs Squeezing vs QuadratureQuadrature
R. Schnabel et al., Class. Quantum Grav. 21, S1045 (2004)]
101
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10410
-24
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10-21
Frequency [Hz]
h [
/H
z]substrate, loss =1e-7substrate, loss =5e-9
Assume: Assume: – Loss in Suprasil = 5 x 10Loss in Suprasil = 5 x 10-9-9
In this case we would then be limited by coating thermal noise In this case we would then be limited by coating thermal noise strong interest in strong interest in reducing coating dissipationreducing coating dissipation
Limit set by coating thermal noise alone
Estimated GEO600 thermal Estimated GEO600 thermal noise – high Q valuenoise – high Q value
Possible improvements to Possible improvements to thermal noise limited thermal noise limited
sensitivity of GEO for better sensitivity of GEO for better coatingscoatings
101
102
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10410
-24
10-23
10-22
10-21
Frequency [Hz]
h [
/H
z]
substrate, loss = 5e-9
Standard coating+substrateCoating using doped Ta2O5
Doped coating+substrateReduced coating noise using Non-Standard Periodicity (NSP) ?????– Pinto et alNSP coating+substrate
Thermal noise from:
4
standard coating
Studies of coating loss ongoing – (see poster by G. Cagnoli)
102
103
104
10-24
10-23
10-22
Frequency [Hz]
h [H
z-1/2
]GEO-HF noise levels based on best possible coating losses
full coating, silicadoped coating, silicaaperiodic coating, silicasilica substrateaperiodic coating, sapphiresapphire substrateaperiodic coating, siliconsilicon substrate
GEO Simulated Noise – GEO Simulated Noise – high Q high Q
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10-18
[h*H
z-1/2
]
Freq. [Hz]
Seismic
Suspension TN
Substrate TN
Coating TN
Thermorefractive
Shot
Total
Studies of silicon as a test mass Studies of silicon as a test mass substratesubstrate
Preliminary Preliminary room T measurementsroom T measurements made of mechanical dissipation of made of mechanical dissipation of bulk silicon samples suspended on bulk silicon samples suspended on silk thread or wire loopssilk thread or wire loops– Internal resonant modes of the samples Internal resonant modes of the samples
excited; decay of mode amplitude excited; decay of mode amplitude measuredmeasured
To high voltage
Excitation plate(behind mass)
Silicon samples cut along different crystal axes, [111] and [100]. The [111] sample was boron-doped.
Dissipation of two silicon samples of identical geometry, supplied by collaborators in Stanford, was measured over a range of frequencies.
Clamp
Suspension thread/wire
Schematic diagram of front view of suspended test mass.
Test mass
Shot Noise in SR IFOsShot Noise in SR IFOs
101
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Freq. [Hz]
ASD
[h/
Hz]
GEO Theoretical Noise Budget
SeismicCoating TNThermorefractiveShot 1 kHzShot 200HzShot 500Hz
102
103
10-21
10-20
10-19
10-18
10-17
Frequency [Hz]
h(t
) [H
z-1/2
]
Jan 02
Aug 02 (S1)
Jan 04 (S3)
Sept 05
Feb 05 (S4)
Aug 04
GEO600 sensitivity evolutionGEO600 sensitivity evolution