LIGO G0900207
Design constraints and optimization for a white light cavity
based GW interferometer including power and signal recycling
Selim Shahriar, Northwestern University
Laboratory of Atomic and Photonic Technologies
L
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.A
.
P
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T
URL: http://lapt.ece.northwestern.edu
Northwestern University Gravitational Wave Astrophysics
Workgroup (Head: Vicky Kalogera)
LVC Meeting 2009: AIC Workgroup: Shahriar / LIGO G0900207
White Light Cavity: Basic Idea
Negative Dispersion
Medium
Source Laser
=2Co/(n)
• Ideal WLC is infinitely broadened, without any drop in storage time / sensitivity
• Ideal WLC is also infinitely sensitive to variation in cavity length
• In practice, broadening and sensitivity limited by finite bandwidth of negative dispersion
LVC Meeting 2009: AIC Workgroup: Shahriar / LIGO G0900207
Active Superluminal Cavity: Superluminal Ring Laser (SRL)
Neg Dispersion
Medium
Beat Signal
• Frequency change is enhanced in sensitivity by a factor of 10 million
• Beat note does not experience the broadening effect
LVC Meeting 2009: AIC Workgroup: Shahriar / LIGO G0900207
Demonstration of White Light Cavity
LVC Meeting 2009: AIC Workgroup: Shahriar / LIGO G0900207
1 (a)i
0.5
0
1
ii
0.5
0
1
iii
0.5
0
1
iv
0.5
0
1
v
0.5
0
-15
-10
cavity res.
 = 8 MHz
18
cavity LW (MHz)
cavity transmission
Demonstration of White Light Cavity
12 MHz
19 MHz
23 MHz
-5
0
5
10
(c)
(c)
14
12
10
8
6
15
10
(b) i
1
3000
0.5
0
1
0.5
0
1
0.5
ii
8 MHz
iii
12 MHz
iv
19 MHz
2500
2000
1500
1000
500
0
-3
v
0
-15
25
empty cavity
WLC
(d)
cavity buildup
cavity transmission
0
1
20
cavity res.
0
1
0.5
15
gain separation (MHz)
frequency (MHz)
0.5
o expt. data
estimated
16
23 MHz
-10
-5
0
5
10
-2
-1
0
1
2
3
frequency (MHz)
15
frequency (MHz)
G.S. Pati, M. Messal, K. Salit, M.S. Shahriar, “Demonstration of a tunable-bandwidth white light
interferometer using anomalous dispersion in atomic vapor,” Phys. Rev. Lett. 99, 133601 (2007)
LVC Meeting 2009: AIC Workgroup: Shahriar / LIGO G0900207
Demonstration of White Light Cavity
0.07
Theory
0.06
0.05
1
mag. (a.u.)
cavity transmission
1.2
Experiment
-/500
/400
0.8
0.6
0.04
0.03
0.4
0.02
0.2
0.01
0
-6
-4
-2
0
2
frequency (MHz)
4
6
8
-10
-5
0
frequency (MHz)
5
10
G.S. Pati, M. Messal, K. Salit, M.S. Shahriar, Optics Communications, 281 (19), p.4931-4935, (2008)
LVC Meeting 2009: AIC Workgroup: Shahriar / LIGO G0900207
Fast-light in Photorefractive Crystal for WLC
H.N. Yum, M. Salit, G.S. Pati, S. Tseng, P.R. Hemmer, and M.S.Shahriar, Optics Express, Vol. 16
Issue 25, 20448 (2008)
LVC Meeting 2009: AIC Workgroup: Shahriar / LIGO G0900207
Fast-light in Photorefractive Crystal for WLC
LVC Meeting 2009: AIC Workgroup: Shahriar / LIGO G0900207
Fast-light in Photorefractive Crystal for WLC
LVC Meeting 2009: AIC Workgroup: Shahriar / LIGO G0900207
Fast-light in Photorefractive Crystal for WLC
LVC Meeting 2009: AIC Workgroup: Shahriar / LIGO G0900207
Fast-light in Photorefractive Crystal for WLC
LVC Meeting 2009: AIC Workgroup: Shahriar / LIGO G0900207
Simple (Meers) Model for Signal and Power Recycling
NPBS
Power Recycling Mirror
Signal Recycling Mirror
detector
LVC Meeting 2009: AIC Workgroup: Shahriar / LIGO G0900207
Enhancing the bandwidth-sensitivity product
Laser
PRM
SRM
det
Intracavity
Intensity
Narrowband
Operation
Intracavity
Broadband
Intensity
Operation
Narrowband
Operation
Broadband
Operation
GW Frequency
GW Frequency
Intracavity
Intensity
WLC
Intracavity
Operation
Intensity
Laser
WLC
Operation
PRM
Narrowband
Operation
Narrowband
Operation
GW Frequency
WLC element
SRM
det
LVC Meeting 2009: AIC Workgroup: Shahriar / LIGO G0900207
GW Frequency
Enhancing the bandwidth-sensitivity product
20
10
5
2
1
0.5
0.2
100
200
500
1000
2000
LVC Meeting 2009: AIC Workgroup: Shahriar / LIGO G0900207
5000
Enhancing the bandwidth-sensitivity product
100
WLC / TSRM =0.001
50
No WLC / TSRM =0.001
10
WLC / TSRM =0.1
5
No WLC / TSRM =0.1
1
0.5
No WLC / TSRM =1
100
200
500
1000
LVC Meeting 2009: AIC Workgroup: Shahriar / LIGO G0900207
2000
5000
Signal and Power Recycling in the Presence of Arm Cavities
LVC Meeting 2009: AIC Workgroup: Shahriar / LIGO G0900207
compound mirror
for signal recycling
Signal and Power Recycling in the Presence of Arm Cavities
compound mirror
for pump recycling
LVC Meeting 2009: AIC Workgroup: Shahriar / LIGO G0900207
Sensitivity-Bandwidth Enhancement for AdLIGO Configuration
WLC element
WLC element
LVC Meeting 2009: AIC Workgroup: Shahriar / LIGO G0900207
compound mirror
for WLC signal recycling
Sensitivity-Bandwidth Enhancement for AdLIGO Configuration
Signal
Extraction
Cavity (SEC)
compound mirror
for WLC pump recycling
LVC Meeting 2009: AIC Workgroup: Shahriar / LIGO G0900207
Sensitivity-Bandwidth Enhancement for AdLIGO Configuration
LVC Meeting 2009: AIC Workgroup: Shahriar / LIGO G0900207
Sensitivity-Bandwidth Enhancement for AdLIGO Configuration
7
Tuned Mode
6
Detuned by 20 deg
5
Detuned by 25.2 deg
Detuned by 36 deg
Detuned by 54 deg
4
3
Without WLC
2
1
14
200
400
600
800
1000
12
With WLC
10
8
6
4
2
200
400
LVC Meeting 2009: AIC Workgroup: Shahriar / LIGO G0900207
600
800
1000
Sensitivity-Bandwidth Enhancement for AdLIGO Configuration
7
Tuned Mode
6
Detuned by 20 deg
Detuned by 25.2 deg
Detuned by 36 deg
Detuned by 54 deg
5
4
3
Without WLC
2
1
200
400
600
800
1000
14
12
With WLC
10
8
6
4
2
200
400
LVC Meeting 2009: AIC Workgroup: Shahriar / LIGO G0900207
600
800
1000
Proposal for Adding an Auxiliary Mirror for Practical WLC
Match SRM to
Input Test Mass
and tune SEC
to resonance
compound mirror
for pump recycling
LVC Meeting 2009: AIC Workgroup: Shahriar / LIGO G0900207
Proposal for Adding an Auxiliary Mirror for Practical WLC
WLC
Element
WLC
Element
compound mirror
for pump recycling
LVC Meeting 2009: AIC Workgroup: Shahriar / LIGO G0900207
WLC
Element
Proposal for Adding an Auxiliary Mirror for Practical WLC
LVC Meeting 2009: AIC Workgroup: Shahriar / LIGO G0900207
Proposal for Adding an Auxiliary Mirror for Practical WLC
100
WLC / TASRM =0.001
50
No WLC / TASRM =0.001
10
WLC / TASRM =0.1
5
No WLC / TASRM =0.1
1
0.5
No WLC / TASRM =1
100
200
500
1000
2000
M. Salit and M.S. Shahriar, “Enhancement of Sensitivity-Bandwidth Product of Interferometric Gravitational
Wave Detectors using White Light Cavities,” (http://arxiv.org/ftp/arxiv/papers/0809/0809.4213.pdf)
LVC Meeting 2009: AIC Workgroup: Shahriar / LIGO G0900207
5000
Active Sagnac Ring Laser in a WLC for Enhancing Strain Sensitivity
Phase Shift Without Anomalous Dispersion
t
h
t 
2
  
Cos (g t ')dt '   o dt '
Phase Shift With Anomalous Dispersion
t
t
t 
t 
ENH   dt '  
t
t 
t
1
1 h
o dt '  
Cos(g t ')dt '
t


ng
ng 2
M.S. Shahriar and M. Salit, (2008) Journal of Modern Optics Vol. 55, Nos.
19–20, 10–20 November 2008, 3133–3147
M. S. Shahriar and M. Salit, “A Fast-Light Enhanced Zero-Area Sagnac Ring Laser Gravitational
Wave Detector,” (http://lapt.eecs.northwestern.edu/preprints/FE-ZASRLGWD.pdf)
LVC Meeting 2009: AIC Workgroup: Shahriar / LIGO G0900207
Journal publications and preprints
G.S. Pati, R. Tripathi, V. Gopal, M. Messal, Phys. Rev. A 75, 053807 (2007)
G.S. Pati, M. Messal, K. Salit, M.S. Shahriar, Phys. Rev. Lett. 99, 133601 (2007)
M. Salit, G.S. Pati, K. Salit, and M.S. Shahriar, (2007) Journal of Modern
Optics, 54:16, 2425 - 2440
G.S. Pati, M. Messal, K. Salit, M.S. Shahriar, Optics Communications, 281
(19), p.4931-4935, (2008)
H.N. Yum, M. Salit, G.S. Pati, S. Tseng, P.R. Hemmer, and M.S.Shahriar,
Optics Express, Vol. 16 Issue 25, 20448 (2008)
M.S. Shahriar and M. Salit, (2008) Journal of Modern Optics Vol. 55, Nos.
19–20, 10–20 November 2008, 3133–3147
M. S. Shahriar and M. Salit, “A Fast-Light Enhanced Zero-Area Sagnac Ring Laser
Gravitational Wave Detector,” (http://lapt.eecs.northwestern.edu/preprints/FEZASRLGWD.pdf)
M. Salit and M.S. Shahriar, “Enhancement of Sensitivity-Bandwidth Product of
Interferometric Gravitational Wave Detectors using White Light Cavities,”
(http://arxiv.org/ftp/arxiv/papers/0809/0809.4213.pdf)
LVC Meeting 2009: AIC Workgroup: Shahriar / LIGO G0900207
LVC Meeting 2009: AIC Workgroup: Shahriar / LIGO G0900207