Differences between revisions 1 and 55 (spanning 54 versions)

Arm Length Stabilization by injecting green laser beams from the arm ends

<<TableOfContents: execution failed [Argument "maxdepth" must be an integer value, not "[2]"] (see also the log)>>aLIGO ALS wiki

http://ilog.ligo-wa.caltech.edu:7285/advligo/Arm_Length_Stabilisation

Plan

time line

time line describes where we are now and where we go.

Conceptual design

Description of the optical / servo configuration [https://dcc.ligo.org/cgi-bin/private/DocDB/ShowDocument?docid=6888 LIGO DCC]
Servo modeling (SimLink) [https://nodus.ligo.caltech.edu:30889/svn/trunk/docs/upgrade08/Green_Locking/Servo_modeling/ 40mSVN]

Detailed design

Design and Purchasing Lists
- Optical design / item list
- Electronics / control design / item list
- Purchase list
Detailed considerations
- Optical Layout ([attachment:green_optics.png Table]/ In-vac)
  - ETM / end table
  - ITM wedge effect
  - Periscopes for beam steering from PR3/SR3 transmissions to the PSL viewport
  - PSL viewport modification (viewport cover / tube / PSL box / periscope on the PSL table)
  - PSL table
  - Laser & SHG specs --- power, polarization, Xtals
    - - references
    - [1] G.D.Boyd and D.A. Kleinman, [http://jap.aip.org/japiau/v39/i8/p3597_s1 "Parametric interaction of Focused Gaussian Light Beams", J.A. Phys. 39, 3597 (1968)]
    - [2] C. Zhang, Y.Qin and Y.Zhu, [http://www.opticsinfobase.org/ol/abstract.cfm?uri=ol-33-7-720 "Perfect quasi-phase matching for the third-harmonic generation using focused Gaussian beams",Opt. Lett. 33, 720 (2008)]
- Main optics specs (review)
- Mode matching ([attachment:modematch_END.png mode matching at end table])
- Green generation
  - [attachment:manual_oven.pdf manual for the covesion oven]
- Expected performance / noise / control system range
- Digital servo / operation
- Alignment (initial / fine / automatic)

Green Preliminary Design: ETM region

attachment:green_ETM_preliminary_design.png

Green Preliminary Design: Vertex region

attachment:green_vertex_preliminary_design.png

Development roadmap

End table arrangement
- NPRO placement / optical assembly at the end
- SHG at the end table
- Control system placement
- Coarse alignment to the cavity
- Fine alignment
- Lock of the green beam to the cavity
At the PSL table
- SHG at the PSL table
Digital control
- Virtual Green lock by RCG
- GPIB interfaces
Vertex tank optical arrangement
- In-vac steering (PO transmission / Periscope / Mirrors)
- Vertex phase noise measurement
  - Electronics placement
  - Control system implementation
Performance evaluation
- f_noise of green beam / PDH performance
- Relative f_noise between the PSL green and the Arm transmitted green
- ALS performance
Sophistication of the scheme
- Automatic handing off scripts
- Ready-to-go panels for AdvLIGO
- Automatic alignment of the green beam
- ---
- Green Michelson for precise ETM calibration
- Absolute length / mode spacing measurement by green

Control information

Laser Frequency vs Crystal Temperature

Plots of the laser frequency vs temperature (measured by beating against a second laser) are shown below. [http://nodus.ligo.caltech.edu:8080/40m/2794 Also, see the elog here].

Laser	df/dT	df/dV - within a mode	df/dV - average
Lightwave	2.8MHz/mK	5GHz/V	1.6GHz/V
Innolight	3.3MHz/mK

Lightwave laser

attachment:lightwave_temperature_sweep.png

Innolight laser

attachment:innolight_temperature_sweep.png

Noise Requirements

jump to Noise Requirement

-  ⇤ ← Revision 1 as of 2009-08-25 00:19:19 → 
  Size: 199
  Editor: YoichiAso
  Comment: u
+   ← Revision 55 as of 2010-04-27 21:54:11 → ⇥
  Size: 4072
  Editor: KiwamuIzumi
  Comment:
-Deletions are marked like this.
+Additions are marked like this.
 Line 1:
-= Green Laser Injection for Arm Pre-Lock =
+= Arm Length Stabilization by injecting green laser beams from the arm  ends =
<<TableOfContents([2])>>aLIGO ALS wiki
-Line 3:
+Line 4:
-We plan to install green lasers, which are phase locked to the PSL laser, at each end station to pre-lock the arm cavities before the lock acquisition.
+http://ilog.ligo-wa.caltech.edu:7285/advligo/Arm_Length_Stabilisation

-------
-------

== Plan ==
=== time line ===
 * [[Upgrade 09/GreenLock/timeline|time line]] describes where we are now and where we go.


=== Conceptual design ===
 * Description of the optical / servo configuration [https://dcc.ligo.org/cgi-bin/private/DocDB/ShowDocument?docid=6888 LIGO DCC]
 * Servo modeling (!SimLink) [https://nodus.ligo.caltech.edu:30889/svn/trunk/docs/upgrade08/Green_Locking/Servo_modeling/ 40mSVN]

=== Detailed design ===
 * '''Design and Purchasing Lists'''
  * Optical design / [[Upgrade 09/Purchase List/Green Locking|item list]]
  * Electronics / control design / [[Upgrade 09/Purchase List/Green Locking|item list]]
  * [[Upgrade 09/Purchase List/Green Locking|Purchase list]]
 * '''Detailed considerations'''
  * Optical Layout ([attachment:green_optics.png Table]/ In-vac)
   * [[Upgrade 09/GreenLock/end table|ETM / end table]] <<ImageLink(endtable.jpg,Upgrade 09/GreenLock/end_table)>>
   * [[Upgrade 09/Optical Layout#wedge|ITM wedge effect]]
   * [[Upgrade 09/Optical Layout|Periscopes for beam steering from PR3/SR3 transmissions to the PSL viewport]]
   * PSL viewport modification (viewport cover / tube / PSL box / periscope on the PSL table)
   * PSL table
   * Laser & SHG specs --- power, polarization, Xtals
    . '' - references''
    . [1] G.D.Boyd and D.A. Kleinman, [http://jap.aip.org/japiau/v39/i8/p3597_s1 "Parametric interaction of Focused Gaussian Light Beams", J.A. Phys. 39, 3597 (1968)]

    . [2] C. Zhang, Y.Qin and Y.Zhu,  [http://www.opticsinfobase.org/ol/abstract.cfm?uri=ol-33-7-720 "Perfect quasi-phase matching for the third-harmonic generation using focused Gaussian beams",Opt. Lett. 33, 720 (2008)]

  * Main optics specs (review)
  * Mode matching ([attachment:modematch_END.png mode matching at end table])
  * Green generation
   . [attachment:manual_oven.pdf manual for the covesion oven]
  * Expected performance / noise / control system range
  * Digital servo / operation
  * Alignment (initial / fine / automatic)

==== Green Preliminary Design: ETM region ====
attachment:green_ETM_preliminary_design.png

==== Green Preliminary Design: Vertex region ====
attachment:green_vertex_preliminary_design.png

=== Development roadmap ===
 * '''End table arrangement'''
  * NPRO placement / optical assembly at the end

  * SHG at the end table
  * Control system placement
  * Coarse alignment to the cavity
  * Fine alignment
  * Lock of the green beam to the cavity
 * '''At the PSL table'''
  * SHG at the PSL table
 * '''Digital control'''
  * Virtual Green lock by RCG
  * GPIB interfaces
 * '''Vertex tank optical arrangement'''
  * In-vac steering (PO transmission / Periscope / Mirrors)
  * Vertex phase noise measurement
   * Electronics placement
   * Control system implementation
 * '''Performance evaluation'''
  * f_noise of green beam / PDH performance

  * Relative f_noise between the PSL green and the Arm transmitted green
  * ALS performance
 * '''Sophistication of the scheme'''
  * Automatic handing off scripts

  * Ready-to-go panels for AdvLIGO
  * Automatic alignment of the green beam
  * ---
  * Green Michelson for precise ETM calibration

  * Absolute length / mode spacing measurement by green''' '''

----
== Control information ==
=== Laser Frequency vs Crystal Temperature ===
Plots of the laser frequency vs temperature (measured by beating against a second laser) are shown below. [http://nodus.ligo.caltech.edu:8080/40m/2794 Also, see the elog here].

|| '''Laser''' || '''df/dT''' || '''df/dV - within a mode''' || '''df/dV - average''' ||
|| Lightwave ||   2.8MHz/mK ||       5GHz/V ||  1.6GHz/V ||
|| Innolight ||   3.3MHz/mK || || ||


==== Lightwave laser ====
attachment:lightwave_temperature_sweep.png

==== Innolight laser ====
attachment:innolight_temperature_sweep.png

= Noise Requirements =
[[Upgrade 09/GreenLock/Noise Requirement|jump to Noise Requirement]]