Clocklaser
Put a paper infront R1 and R2, when beam adjustment! Too high input power can damage the mirrors of the resonator!
Typical values and datasheets of the clocklaser system
Laserdiode (ECDL)
Tapered Amplifier (TA)
Light with input power of min 10mW must pass TA! Maximum current is 3A. Otherwise the TA will be broken
Turning on and off the clocklaser system
Turning on the laser
We use toptica electronics:
Turning the main-key to on. The LED´s from the temperature control will go on!
Push the green button. The green LED from the button will go on!
Switch on the toggle (=Kippschalter) of the laserdiode controller. The green LED of the laserdiode controller will go on!
Switch on the toggle of the TA, if he is seeded! The green LED of the TA controller will go on!
Note: If the switches are on, then not steps 3. & 4.
Turning off the laser
Note: Both toggles to switch off the laserdiode and TA are not required!
Push the red button. The green LED will go out!
Turning the main-key to “mains”
Only turning off the laserdiode
Switch off the toggle from the TA. The green LED from the TA module will go out!
Switch off the toggle from the laserdiode. The green LED from the laserdiode module will go out!
Only turning off the TA
Switch off or on the toggle from the TA. The green LED from the TA module will go out!
Fast Locking of R1
Check laser frequency with wavemeter: XXX
Check laser power @ upstairs PD: Display should shown stop position
Check modes of scan cavity: Has to be single mode
Note: If cases 1, 2 and 3 are given, then lock the laser like:
XXX Das darfst du schreiben mit welchen Knopf wann gedrückt wird
XXX
XXX
Errors
A) To less power @ upstairs PD
B) To less power @ scan cavity
C) Acoustic Signal of TA controller
Solution of A, B and C: In most cases it is sufficient to increase incouple power of TA
Necessary lock power: ~200mW An welcher Stelle?
turn off the TA lock:
turn off the I and P switch
Note: D is always off
Adjust the incoupling power in the TA with mirror XYZ in vertical direction until Errors A and B are fixed
Lock of TA
If the incoupling is good → ∼1A - after TA (Pos.C): ~200mW
Power up the clocklaser system
Laser
Check power of Laserdiode direct after laser housing (Pos.A)
TA Lock
first Check:
Info: necessary lock power: 200mW
If the incoupling is good → ∼1A - after TA (Pos.C): ~200mW
fast acoustic Signal means the powerstabilisation warning (lock power too low gibt es noch andere Gründe?)
If the incoupling is bad (frequent cause of powerstabilisation warning/ show “error 1”):
P-Stab. off (PID) & block the beam!
adjust mirror MTA (horizontal beam way); references are the peaks (CH4) of Single-Mode-Signal (show “ideal situation”)
Test and switch on the P-stab. (beam is blocked!): warn signal on?
if the acoustic signal is off > measure the incoupling power (Pos.E) max. ~120müW
Lock the Resonator
R1
Modelocking of R1
Tune the Piezo upto TEM00 is observable
if necessary use Mode-Reset
Intensity Lock of R1
after Isolator (ISO3) direct infront R1 (Pos.E): max. ~120müW / min. ~100müW
otherwise improve the optical way to the Isolator for more power
mit Output Offset des Intenstitäts-PID auf 100müW herunterdrehen
HENCE: Check always Power after Isolator of R1: not more than 100müW!!!
Only aktivate PDH/TA-Lock + couple into R1, if the power is 100(±20)müW after the Isolator of R1
Modelocking of R1 (Step 1)
Lock RAM
Lock Fiberstabilization
Littmann design
Typical efficiencies at 916 nm:
Isolators: 80 %
AOMs: 50-60 %
Fiber coupling: 50 %
Typical values for the laser:
Frequency: 327.5293 THz (doubled upstairs directly behind SHG: 655.058 566 THz)
Frequency: 327.5294 THz [Sep, 2019]
Power after ECDL (Pos.A):
Power front of TA (Pos.B):
Power after TA (Pos.C):
~290 mW (@~1364 mA) [Sep, 2019]
~XX mW (@ ~1165 mA) [2018]
~200 mW (@ ~1000 mA) [2016]
Power after TA (Pos.D):
Power in front of ISO3
Power in front of ISO3
TA current should be <1.2A noch richtig, wenn jetzt 1,4A? otherwise the fiber stabilization will soar (=aufschwingen)
Typical values in front fibers:
Typical values after fibers:
Typical values for the resonators:
In front of telescope: 2.2 mW
In front of AOM: 1.5 mW
In front of fiber: 450 µW
100 µW between Isolator and BS
50 µW in front of Resonator
Typical values for locking signals:
PDH error signal locked ~500 mV PP / unlocked ~200 mV PP
Intensity Error signal ~2 mV PP / DC:
Fiber Stabilization Locked ~200 mV PP / Unlocked ~2 Volt PP
Manuals and Datasheets