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)

Datasheet

Testsheet [Serial Number: BA-02465]

Testsheet [Serial Number: BA-02464]

Temperature Laserdiode (marking 1):

act: 24,4°C [Sep, 2019]

set: 24,4°C [Sep, 2019]

min-max: 15°C - 35,1°C [Sep, 2019]

act: 24,5°C [2018]

Typical Current Laserdiode (marking 1):

act: 98 mA [Sep, 2019]

set: 97/98 mA [Sep, 2019]

act: 96 mA [2018]

Tapered Amplifier (TA)

Typ: EYP-TPA-0915-01500

Datasheet: EYP-TPA-0915-01500

Light with input power of min 10mW must pass TA! Maximum current is 3A. Otherwise the TA will be broken

Temperature TA (marking 2):

act: 20°C [Sep, 2019]

set: 20,1°C [Sep, 2019]

min-max: 15 - 35,1°C [Sep, 2019]

act: 20°C [2018]

Typical Current TA (marking 2):

act: 1364/ 1453 mA [Sep, 2019] wieso zwei verschiedene Werte? Beim Einschalten PID wird Strom größer

act: 1201 mA [Nov, 2019 nach Einstellen l/2, um mehr Leistung an Leistungsstab. zur Verfügung zu stellen ]

set: 1464 mA [Sep, 2019]

max < 1,5 A

act: 1176 mA [2018]

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):

~11,2 mW (@~97/98 mA) [Sep, 2019]

~12 mW (@ ~90 mA) [2016]

~XX mW (@ ~96 mA) [2016]

Power front of TA (Pos.B):

~ 9 mW [Sep, 2019]

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):

~ 230 mW (@~1364 mA) [Sep, 2019]

Power in front of ISO3

~ 135müW (@~1364 mA TA) [Sep, 2019]

Power in front of ISO3

~ 120müW (@~1364 mA TA) [Sep, 2019]

TA current should be <1.2A noch richtig, wenn jetzt 1,4A? otherwise the fiber stabilization will soar (=aufschwingen)

Typical values in front fibers:

Power before fiber for wavemeter/comb/mode analysis cavity:

~12 mW [2016]

~XX mW [2018]

Power before AtomLabFiber:

~30 mW → 15 mW upstairs before TA [2016- without fiber stabilization]

~XX mW → 20 mW upstairs before TA [2018]

Power to R2:

~2.5 mW [2016]

~XX mW [2018]

Typical values after fibers:

Power before fiber for

Comb:

~XX mW [2018]

Wavemeter:

~XX mW [2018]

Scan cavity:

~XX mW [2018]

Power after AtomLabFiber:

20 mW upstairs before TA [2018]

Power after R2 fiber:

~XX mW [2018]

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