2024-05-08 14:47:05 -04:00
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:PROPERTIES:
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:ID: d7630955-6ca9-4de7-9770-2d50d4847bcd
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:END:
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#+title: Fitting Ringdown
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2024-05-08 20:50:40 -04:00
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2024-05-09 10:55:28 -04:00
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* Fitting transients
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- one can solve the equation of motion for when a mode is in the
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steady state and the laser is suddenly switched. one obtains a
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decaying oscillation which can be fitted to the data.
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- this works ok, when the system /was/ in the steady state before the jump
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- see [[file:scripts/transients_without_amplification.py]]
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- we obtain \(γ\approx\SI{2.2}{\kilo\hertz}\) but this can vary a lot
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- the detuning frequency seems to be completely off
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2024-05-08 20:50:40 -04:00
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* Failure of the steady state
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On the right peak on can see that there might be something fish going
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on. This is ~data/24_05_24/nice_transient2~.
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[[file:figures/non_steady.png]]
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2024-05-09 10:55:28 -04:00
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* Weird Oscillations :ATTACH:
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- when turning on the amp while the laser is running we get some
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oscillations at \(\sim \SI{40}{\kilo\hertz}\) which is a period of
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\(\SI{25}{\micro\second}\). this is 500 times roundrip time :(). I
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thought it might be a wave packet traveling around the loop, i.e
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multiple modes together...
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[[attachment:osci_closeup.png][osci_closeup.png]]
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[[attachment:osci_far.png][osci_far.png]]
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[[attachment:cleaned.png][cleaned.png]]
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- it isn't close to the fsr though...
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- fitting a sine to that gives pretty much the same, as does an fft
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[[attachment:cleaned_fit.png][cleaned_fit.png]]
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- it is pretty constant over all steps in [[file:data/09_05_24/Nicely_hybridised_2 2024,05,09, 15h57min00sec/][data]] as can be ascertained
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from [[file:scripts/weird_oscillations.py][this script]]
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- these are also present w/o the amp cutout!
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[[attachment:osci_without.png][osci_without.png]]
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