Next%20generation%20nonclassical%20light%20sources%20for%20gravitational%20wave%20detectors

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Next generation nonclassical light sourcesfor
gravitational wave detectors

• Stefan Ast, Christoph Baune, Jan Gniesmer, Axel
  Schönbeck, Christina Vollmer, Moritz Mehmet,
  Henning Vahlbruch, Hartmut Grote, Lisa Kleybolte,
  Alexander Khalaidovski and Roman Schnabel
• Institut für Laserphysik, Universität Hamburg
• Albert-Einstein-Institut, Max-Planck-Institut für
  Gravitationsphysik
• Institut für Gravitationsphysik der Leibniz
  Universität Hannover

Rencontres de Moriond 2015
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The GEO 600 squeezed light source
The LIGO Scientific Collaboration, A
gravitational wave observatory operating beyond
the quantum shot-noise limit, Nature Physics 7
(2011)
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The GEO 600 squeezed light source
Duty cycle 85 (2011-2015)
Max. 3.7 dB
The LIGO Scientific Collaboration, A
gravitational wave observatory operating beyond
the quantum shot-noise limit, Nature Physics 7
(2011)
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Einstein Telescope I artistic layout
M Punturo et al, The Einstein Telescope a
third-generation gravitational wave observatory,
Class. Quantum Grav. 27 (2010)
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Einstein Telescope II Interferometer designs
1550 nm
M Punturo et al, The Einstein Telescope a
third-generation gravitational wave observatory,
Class. Quantum Grav. 27 (2010)
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High conversion efficiency second harmonic
generation

• Ast et al. High-efficiency frequency doubling of
  continuous-wave laser light
• Optics Letters 36 (2011) No. 17

Rencontres de Moriond 2015
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Improve SHG conversion efficiency
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Experimental setup High conversion second
harmonic generation
Conversion measurement
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High efficiency second harmonic generation
Power Conversion 1.1 W (1550 nm) ? 1.05 W (775
nm) Power meter error 6 total ? inaccurate!
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SHG pump depletion
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Doubly-resonant squeezed light source at 1550 nm
Kleybolte, Master Thesis 2013
Rencontres de Moriond 2015
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The GEO 600 squeezed light source
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Doubly resonant squeezing resonator _at_ 1550 nm
1 MHz
130 kHz
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Squeezing measurement in the audio band
12.3 dB
Squeezing at 1550 nm strong enough for third
generation GW detectors
Mehmet et al. Squeezed light at 1550 nm with a
quantum noise reduction of 12.3 dB Optics
Express 19 (2011) No. 25
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Frequency conversion of squeezed light

• Baune et al. arXiv1503.02008

Rencontres de Moriond 2015
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DECIGO squeezing _at_ 532 nm
Sum Frequency Generation
532 nm
Kawamura et al, The Japanese space gravitational
wave antenna DECIGO, Class. Quantum Grav. 28
(2011)
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Experimental setup frequency conversion of
squeezed light
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Squeezing measurement _at_ 532 nm
5 dB
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Summary
High-efficiency SHG 95 conversion efficiency _at_
1550 nm
Doubly resonant squeezed light source Maximum of
10 dB _at_ 1 MHz 7 dB _at_ 130 kHz
Squeezed light for 3. generation GWD 12.3 dB _at_
1550 nm
Frequency up-conversion of squeezed light 5 dB _at_
532 nm
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Thank you for your attention!
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Generation of squeezed light
Squeezed bandwidth
Parametric down conversion
Squeezing bandwidth
Pump power enhancement
Squeezing enhancement
FSR
 
Problem R? limits the bandwidth!
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Squeezed light source without squeezing resonator

• S. Ast et al, Continuous-wave nonclassical light
  with gigahertz squeezing bandwidth, Optics
  letters 37, 2367 (2012)

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Outline

• GHz bandwidth quantum states
• Quantum Key Distribution
• High-bandwidth quantum state generation
• GHz bandwidth squeezed light
• GHz bandwidth entangled light

Experiment
Squeezed light via the cascaded Kerr effect An
Odyssey to Kerr squeezing New experimental
approach Cascaded Kerr squeezing
Experiment
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Experimental setup Squeezed light at 1550 nm
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Kerr squeezing loss estimation
Based on 85 mW pump power at 358 MHz
Estimated loss contributions
9.5 dB
Type Detection efficiency
Homodyne efficiency 0.978
PD quantum efficiency 0.94
Optical path loss 0.88-0.92
Bow-tie internal loss 0.547
SEMC transmission 0.887
Total 0.39-0.41
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-2 dB
Bow-tie internal loss High 775 nm generation