Optical dipole trap experiment

Study the trapping and loss characteristics of cold atoms in an ODT with Quatm’s two-parameter scans and lifetime measurements.

Overview

This experiment script provides the class optical_trapping: build() declares the lithium MOT/CMOT and the imaging devices and exposes the key timing parameters for loading / trapping / imaging as GUI parameters; run() orchestrates the complete optical dipole trap (ODT) experiment sequence through methods such as init_CMOT, fluorescence_imaging and absorption_imaging.

Timing stages

MOT loading (Mot_loading) → CMOT (init_CMOT: gradient/detuning/power switching)
  → ODT trapping (trapping_time_ms) → release → time of flight (time_of_flight)
  → absorption imaging / fluorescence imaging

Parameters (build excerpt)

Mot_loading, Flash_us, trapping_time_ms, resonance_shift, image_detuning, detuning_ramp_slope_MHz_ms, time_of_flight, MOT_detuning / CMOT_detuning, MOT_Current_Loading / CMOT_Current and the Homogenous_Current_* series, etc.

Key code (excerpt)

from quatm.experiment import Experiment, NumberValue, delay

class optical_trapping(Experiment):
    def build(self):
        self.setattr_device("li_cooling_aom")
        self.setattr_device("li_absorption_h")
        self.setattr_argument("trapping_time_ms", NumberValue(...))
        # ... remainder omitted

    def init_CMOT(self):
        # CMOT stage: gradient, detuning and power switching
        ...

Companion

The xODT/cODT beam path can be aligned with the dipole-trap optimisation helper; for imaging data analysis see Absorption imaging and Absorption imaging in the data and analysis section.