|
Size: 490
Comment:
|
Size: 3728
Comment:
|
| Deletions are marked like this. | Additions are marked like this. |
| Line 1: | Line 1: |
| = Green Laser Injection for Arm Pre-Lock = | = Arm Length Stabilization by injecting green laser beams from the arm ends = [[BR]] [[BR]] |
| Line 3: | Line 5: |
| 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. | |
| Line 5: | Line 6: |
| == Basic Concept == | <<TableOfContents([2])>> [[BR]] {i} aLIGO ALS wiki http://ilog.ligo-wa.caltech.edu:7285/advligo/Arm_Length_Stabilisation [[BR]] ------- == 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] ==== Green Preliminary Design ==== . <<ImageLink(green_vertex_preliminary_design.png,Upgrade 09/GreenLock/Preliminary design for the vertex,height=200)>> <<ImageLink(green_ETM_preliminary_design.png,Upgrade 09/GreenLock/Preliminary design for the end,height=200)>> === 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''' ''' == 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) == Control information == . B) [[Upgrade 09/GreenLock/Control Information|jump to Control Information]] |
| Line 7: | Line 100: |
| I'd say the arm cavity length should not change more than 1/100 of the resonance width in the time scale of 10sec. For this to be fulfilled, the RMS change of the cavity length must be suppressed below 1e-11m level. Does this make sense ? |
. B) [[Upgrade 09/GreenLock/Noise Requirement|jump to Noise Requirement]] |
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 BR
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]
Green Preliminary Design
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
Detailed design
Design and Purchasing Lists
Detailed considerations
- Optical Layout ([attachment:green_optics.png Table]/ In-vac)
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)
- Optical Layout ([attachment:green_optics.png Table]/ In-vac)
Control information
