Onefive output power, posted by Loïc Amoudry at Optical room about lasers and optics
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The pump voltage has been increased few days ago when looking for a modlock of the laser.
The 33MHz Onefive output power is now 3.58mW with OD1 filter ==> ~36mW.
There are 2µW @ 1% coupling fiber with OD1 filter ==> ~20µW ==> 2mW @99% coupling fiber (2mW to the amplifier). |
Onefive output power, posted by Loïc Amoudry at Optical room about lasers and optics
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Onefive output power measured today. 3.52 mW with OD1 filter ==> ~35mW.
Loïc
Amoudry wrote:
The pump voltage has been increased few days ago when looking for |
Onefive ouput power and spectrum, posted by Loïc Amoudry at Optical room about lasers and optics 
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After turning on, one can see the 133.33MHz Onefive output power for ~40min with OD2 filter (~/20). So the real output power is ~57mW. A measurment over
several days (15?) should come in few weeks.
The spectrum here has been taken one day after turning on the Onefive (see Fig. 133_spectrum_full and 133_spectrum). One can see the central |
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Onefive ouput power and spectrum, posted by Loïc Amoudry at Optical room about lasers and optics
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1) Note: The OneFive laser used for experimenting is the one for the SBox
but, for now only this laser arrived from the company so we are doing tests (measuring the spectrometer and power ) on it inside the ThomX cavity
clean room. |
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Onefive laser modelock and Smaract CEP controller, posted by Ronic Chiche at ThomX igloo about lasers and optics
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today, during an attempt in improving the CEP with the Smaract controller CH2, we lost the laser modelock.
at this point, we decided to reference the Smaract CH2 for CEP :
now, 0 mm is roughly the middle of the motor range. |
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Onefive Origami 33MHz specs - Polarisation, posted by Ronic Chiche at Optical room about lasers and optics
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one rotate a lambda/2 before a PBS and meausure the refected power:
Pmax=35.6 mW
Pmin=107 µW |
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Onefive Origami 33MHz specs, posted by Loïc Amoudry at Optical room about lasers and optics 6x
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Power during ~20h, power after turn on, spectrum image and excel datas, polarisation and pulse length.
Powermeter measurments were done with a /10 filter.. 3 mW means 30 mW
Important: Onefive does not automatically locks after being turned on. |
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Onefive Origami 33MHz specs, posted by Loïc Amoudry at Optical room about lasers and optics
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Beam Size Onefive added
Loïc
Amoudry wrote:
Power during ~20h, power after turn on, spectrum image and excel |
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Onefive 33MHz unmodelocked, posted by Loïc Amoudry at Optical room about lasers and optics
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Oscillator randomly unmodelocked on 3rd july afternoon (during oscillator power measurement, maybe a reflection from the powermeter power filter
?)
Modelocked this afternoon by putting Onefive motor and phase at reference on the PTC software. |
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Onefive 33MHz modelock loss, posted by Ronic Chiche at ThomX igloo about lasers and optics
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On Friday 11th of October, due to the Yvette flooding, all the AC power of ThomX have been shut down.
After the shutdown, I had to restart the Onefive oscillator but the laser modelock was lost.
I had to do a step of 1mm at 10mm/s with the Smaract motor on the rep rate channel (CH1) |
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Onefive 33MHz modelock loss, posted by Ronic Chiche at ThomX igloo about lasers and optics
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This morning, I verified the reason why the seeder frequency was not displayed on the amplifier software screen:
one needs to start the amplifier (even at 0%) to see the seeder frequency !!!
now, we have 33.371MHz as expected ! => OK |
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Onefive 33MHz modelock loss, posted by Ronic Chiche at ThomX igloo about lasers and optics
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After the new Yvette flooding of the last week and the consecutive AC-shut down, I restarted this morning the laser with the same procedure (step of
1mm at 10mm/s with the Smaract motor on the rep rate channel (CH1)).
now, we have again 33.371MHz and 3.1mW input power as expected ! => OK |
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Onefive 33MHz modelock loss, posted by Ronic Chiche at ThomX igloo about lasers and optics
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For the modulation/demodulation generator for the PDH signal,
after a power shutdown, on can :
1) restart the generator to get the correct parameters: |
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Noise issue, posted by Ronic Chiche at ThomX igloo about lasers and optics | detectors and electronics
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since several days, we see that the locking is more and more unstable and the lock duration was sometime less than 20-30 seconds !
1) I tried to optimize the feedback loops
I discovered that the gain on the fast loop on the laser EOM was very low and was almost uneffective for the global stability of the lock (I |
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Noise issue, posted by Ronic Chiche at ThomX igloo about lasers and optics | detectors and electronics
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yesterday, in the same conditions, we had so many locking issues... exactly in the same way than before. :-(
so we still have "locking issues" depending on something we didn't find...
today, we removed the "1/2 voltage divider" before the PZT amplifier to get back the full dynamic. |
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New recipies with additionnal attenuation before the diffuser and new x3 amplifier on laser PZT, posted by Ronic Chiche at ThomX igloo about lasers and optics | detectors and electronics
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With optical attenuation + x3 amplifier on laser PZT channel + feedback tuning
Temporary recipie for ~ 92kW power in the FP-cavity:
(in the previous scheme, without x3 laser PZT amp, a good lock was achieved for a PDH signal power noise ~ 70 mV rms) |
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New recipies with additionnal attenuation before the diffuser, posted by Ronic Chiche at ThomX igloo about lasers and optics | detectors and electronics
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With optical attenuation only
For ~ 92kW power in the FP-cavity:
Alplhanov amplifier ratio : 33% |
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New power record in ThomX cavity, posted by Ronic Chiche at ThomX igloo about lasers and optics
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| today, we were able to store more than 93kW in the FP cavity, always with the same parameter : 33% laser amplifier ratio |
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New power record in ThomX cavity, posted by Ronic Chiche at ThomX igloo about lasers and optics
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today, we were able to store more than 94kW in the FP cavity, always with the same parameter : 33% laser amplifier ratio
Ronic
Chiche wrote:
today, we were able to store more than 93kW in the FP cavity, always |
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New power record in ThomX cavity, posted by Ronic Chiche at ThomX igloo about lasers and optics
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today, we were able to store more than 95kW in the FP cavity, always with the same parameter : 33% laser amplifier ratio
Ronic
Chiche wrote:
today, we were able to store more than 94kW in |