Differences between revisions 14 and 17 (spanning 3 versions)
⇤ ← Revision 14 as of 2019-04-05 00:51:26 →
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Editor: KevinkunsATligoDOTorg
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← Revision 17 as of 2019-04-06 01:59:18 → ⇥
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Editor: KevinkunsATligoDOTorg
Comment:
Deletions are marked like this. Additions are marked like this.
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 1. Cavity design: triangle, quad ring, quad zig-zag (reference the new OMC paper from Koj)  1. Cavity design: triangle, quad ring, quad zig-zag (reference the new OMC paper from Koji)
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 1. Phase noise of LO
 1. Polarization stability requirement for polarization BHD
 1. Backscatter
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==== Modelling/Noise Budget ==== ==== Action items ====
 * SRC design
  * Suppress 02/20 modes
  * Partially transmit 01/10 modes for AS WFS
  * Suppress thermally generated modes
  * After the above have been satisfied, maximize ponderomotive squeezing
 * Budget above noises, but especially investigate polarization stability.
 * How is homodyne angle controlled?
 * Beam routing
  * Where to pick off LO?
  * Can we use ETMX transmission for LO? (Koji is crazy)
 * A+ BHD noise budget for both baseline double OMC and polarization BHD.

==== Modeling/Noise Budget ====

Balanced Homodyne Detection

Requirements

  1. Displacement noise of OMC/LMC mirrors
  2. Scatter loss in mirrors
  3. Cavity design: triangle, quad ring, quad zig-zag (reference the new OMC paper from Koji)
  4. Laser amplitude / frequency noise including DC offsets in various other lock points and motions to simulate bilinear noise
  5. Oscillator noise: AM / FM
  6. Aux length noise: MICH/PRC/ SRC
  7. Req. on offsets/asymmetries: arm finesse, arm reflectivity, mass imbalance of ETMs
  8. Phase noise of LO
  9. Polarization stability requirement for polarization BHD
  10. Backscatter

Action items

  • SRC design
    • Suppress 02/20 modes
    • Partially transmit 01/10 modes for AS WFS
    • Suppress thermally generated modes
    • After the above have been satisfied, maximize ponderomotive squeezing
  • Budget above noises, but especially investigate polarization stability.
  • How is homodyne angle controlled?
  • Beam routing
    • Where to pick off LO?
    • Can we use ETMX transmission for LO? (Koji is crazy)
  • A+ BHD noise budget for both baseline double OMC and polarization BHD.

Modeling/Noise Budget

  • Some BHD modeling is done in the OptimalGWextraction repo here.

Polarization BHD

Balanced Homodyne Detection (last edited 2020-04-29 17:41:39 by JonathanrichardsonATligoDOTorg)