OptimizerStabilizedModulatedLaser#

Class Arguments

Argument

Type

Default Value

optimizer

Optimizer

photodiode

Photodiode

modulator

LightModulator

laser_source

LaserSource

cache_size

TInt32

8

switch

Switchable

None

fm_device

TStr

mod

am_device

TStr

mod

src_transmission

TFloat

1.0

zero_freq

TFloat

None

power

TFloat

0.001

Bold arguments are mandatory. For more documentation on the listed arguments refer to the class definition below. If parameters appear in this list but not in the class definition below, please recursively check the linked base classes for the definition of the parameter.

Inheritance Diagram

Inheritance diagram of atomiq.components.laser.OptimizerStabilizedModulatedLaser

Example Component Dictionary

   {
    "laser_example": {
        "classname": "atomiq.components.laser.OptimizerStabilizedModulatedLaser",
        "arguments": {
            "optimizer": "<mandatory parameter (Optimizer)>",
            "photodiode": "<mandatory parameter (Photodiode)>",
            "modulator": "<mandatory parameter (LightModulator)>",
            "laser_source": "<mandatory parameter (LaserSource)>",
            "cache_size": 8,
            "switch": null,
            "fm_device": "mod",
            "am_device": "mod",
            "src_transmission": 1.0,
            "zero_freq": null,
            "power": 0.001
        }
    }
}

Class Description

class atomiq.components.laser.OptimizerStabilizedModulatedLaser(optimizer, cache_size=8, *args, **kwargs)

Bases: StabilizedModulatedLaser

A modulated laser power-stabilized through an optimizer

This class integrates an optimizer to find the best setting of the amplitude modulator to achieve the desired power on the monitoring photodiode. This can be used to create "poor man's PID". Upon calling :func:set_power() it is checked whether an optimization result for the requested power already exists. If not the optimizer is called to find the best setting. This result is applied to the modulator and stored in the cache.

To find the best setting, the optimizer will (multiple times) switch on the laser, change its power and measure the photodiode. When switching on the light interferes with the experimental sequence, make sure to call :func:set_power() for your desired power for the first time before the experiment starts. Then the optimization will be done when it does not interfere with your experiment and at a later time the optimization result can be read from the cache, i.e. not further optimization is possible. Of course this assumes that the laser source power is reasonably stable during the time between the optimization the the time the value is recalled from the cache.

Parameters:
  • optimizer (Optimizer) -- Optimizer to use for finding the proper setting of the modulator. Make sure that the actor_component of the optimizer is identical to the the lasers modulator and the optimizer's monitor_component is identical to the lasers photodiode.

  • cache_size (TInt32) -- number of optimization results that can be stored. (default 8)

A Switchable has one ore more channel(s) that can be switched on or off

set_power(power)

Set the output power of the laser

If the requested power is not already in the cache, this will immediately perform the optimization and set the result on the modulator. If the requested power is present in the cache, the cache value is used.

Parameters:
  • power (TFloat) -- the power the laser should be stabilized to. If the photodiode is calibrated the power should be

  • units (given in the calibrated) --

arb(duration, samples_amp=[], samples_power=[], samples_freq=[], samples_det=[], samples_phase=[], repetitions=1, prepare_only=False, run_prepared=False, transform_amp=<function identity_float>, transform_freq=<function identity_float>, transform_phase=<function identity_float>)

Play Arbitrary Samples from a List

This method allows to set the output amplitude, frequency an phase according to the values specified in respective lists. The whole sequence is played in the specified duration. The pattern store in the sample list can also be repeated.

We supports a scheme to prepare the arb function before it is actually used. If that is needed, run this function with prepare_only = True when the arb should be prepared and with run_only = True when the prepared arb should be played. In both calls the other parameters have to be passed.

Parameters:
  • samples_amp (TList(TFloat)) -- List of amplitude samples. If this list is empty (default), the amplitude is not modified.

  • samples_power (TList(TFloat)) -- List of power samples. If this list is empty (default), the amplitude is not modified. This overwrites samples_amp.

  • samples_freq (TList(TFloat)) -- List of frequency samples. If this list is empty (default), the frequency is not modified.

  • samples_det (TList(TFloat)) -- List of frequency samples relative to the zero frequency. If this list is empty (default), the frequency is not modified. This overwrites samples_frequency

  • samples_phase (TList(TFloat)) -- List of phase samples. If this list is empty (default), the phase is not modified.

  • duration (TFloat) -- The time in which the whole sequence of samples should be played back [s].

  • repetitions (TInt32) -- Number of times the sequence of all samples should be played. (default 1)

  • prepare_only (TBool) --

  • run_prepared (TBool) --

ramp(duration, frequency_start=- 1.0, frequency_end=- 1.0, amplitude_start=- 1.0, amplitude_end=- 1.0, power_start=- 1.0, power_end=- 1.0, ramp_timestep=- 1.0, ramp_steps=- 1)

Ramp frequency and/or power/amplitude over a given duration.

Parameters default to -1 to indicate no change. If the start frequency/amplitude is set to -1, the ramp starts from the last frequency/amplitude which was set.

Either power or amplitude can be given to ramp the intensity of the laser. If power is given, it overwrites the value for the amplitude

This method advances the timeline by ´duration´

Parameters:
  • duration (TFloat) -- ramp duration [s]

  • frequency_start (TFloat) -- initial frequency [Hz]

  • frequency_end (TFloat) -- end frequency [Hz]

  • amplitude_start (TFloat) -- initial amplitude [Hz]

  • amplitude_end (TFloat) -- end amplitude [Hz]

  • power_start (TFloat) --

  • power_end (TFloat) --

  • ramp_timestep (TFloat) --

  • ramp_steps (TInt32) --

set_frequency(frequency)

Set the absolute frequency of the light after modulation

Parameters:

frequency (TFloat) -- Absolute frequency of the light after modulation in Hz