https://www.quatm.com/en/docs/examples/Recent content in Application examples on QuatmHugoenhttps://www.quatm.com/en/docs/examples/atom-ion-interaction/atomion-collision-experiment/Mon, 01 Jan 0001 00:00:00 +0000https://www.quatm.com/en/docs/examples/atom-ion-interaction/atomion-collision-experiment/Overview This experiment provides the class secondinteraction: it integrates the lithium-atom MOT with ion loading, state preparation and shuttling into one atom–ion collision/interaction experiment. Each stage is encapsulated in its own method, which makes it easy to reuse and extend. Stage methods Method Description load_ions Ablation loading + laser cooling of the ions count_ions Fluorescence counting to determine whether an ion is in the trap Ion_to_D_state / Ion_to_S_state State preparation load_MOT / MOT_off Loads / switches off the lithium MOT ion_state_preparation Ion state preparation before the interaction run Orchestrates the loading–state preparation–collision–detection sequence Parameters (build excerpt) Loading_Time, Nr_Ablation_Pulses, Det_Time, Nr_Pictures, loadingtime_MOT, detection_time, RF_Voltage_Final and others.https://www.quatm.com/en/docs/examples/ultracold-atoms/dipole-trap-optimisation-helper/Mon, 01 Jan 0001 00:00:00 +0000https://www.quatm.com/en/docs/examples/ultracold-atoms/dipole-trap-optimisation-helper/Overview Before an optical dipole trap (xODT/cODT) experiment, the beam has to be aligned onto the atoms/ions with the dipole-trap optimisation helper. The experiment-helper main window odt_utils on the GUI side (quatm/GUI/entries/odt_utils.py) aggregates two kinds of alignment tool as tabs: Tab Real component Purpose xODT alignment alignment/odt_utils.odt piezo-mirror axis scan → Gaussian fit → publish, aligning the xODT/cODT onto the atom cloud Stray-field compensation alignment/odt_utils.compensation find the compensation voltage along each trap axis to minimise the stray field Usage from quatm.https://www.quatm.com/en/docs/examples/ion-trap-experiments/electric-field-offset-compensation-helper/Mon, 01 Jan 0001 00:00:00 +0000https://www.quatm.com/en/docs/examples/ion-trap-experiments/electric-field-offset-compensation-helper/Overview Ion-trap experiments are often affected by stray electric fields (ion-position offsets/micromotion). The electric-field offset compensation helper brings together voltage scanning, data plotting and the determination of the compensation voltage: on the GUI side it is provided by CompensationHelper in quatm/GUI/alignment/comp_helper.py; on the experiment side Usage Example/experiments/compensation.py (class compensation) applies shim voltages to the ion and triggers multi-frame images, scanning axes such as trap_x / trap_y. GUI components (comp_helper) Component Description Compensation Compensation main panel (one plot per trap axis + controls) PlotWidget / TabWidget Plot with one tab per trap axis ControlWidget / SingleAxisWidget Scan controls per axis and “find the compensation voltage” (intersection of two fitted lines) CompVoltageScan Executes a voltage scan on the rf confinement Usage from quatm.https://www.quatm.com/en/docs/examples/ion-trap-experiments/ion-loading-and-cooling/Mon, 01 Jan 0001 00:00:00 +0000https://www.quatm.com/en/docs/examples/ion-trap-experiments/ion-loading-and-cooling/Overview This script provides the class loading_ion: it orchestrates the complete ion-loading routine from switching on the RF trap, producing ions by ablation and laser cooling through to fluorescence detection. The number of ablation pulses, the pulse width and the cooling/detection durations are all GUI parameters. Parameters (build excerpt) Nr_Ablation_Pulses, tune_pulse_number, pulse_duration, det_time, shutter_time, V_rf (trap voltage), ion_cool_power. Timing Switch on the RF trap (V_rf) → ablation pulses (several) → laser cooling → fluorescence detection (count to decide whether the ion loaded successfully) Key code (excerpt) from quatm.https://www.quatm.com/en/docs/examples/ultracold-atoms/mot-loading-optimisation/Mon, 01 Jan 0001 00:00:00 +0000https://www.quatm.com/en/docs/examples/ultracold-atoms/mot-loading-optimisation/Overview This experiment script provides the class mot_settings: build() declares the full set of lithium MOT/CMOT devices and exposes the axial / radial magnetic-field currents and the MOT/CMOT detunings as GUI parameters, so that the magneto-optical trap loading can be optimised manually or by scanning. run() contains an empty timing sequence, on top of which imaging/counting can be added to assess the loading. Devices (build excerpt) Device Purpose li_cooling_aom / li_repump_aom / li_zeeman_aom cooling / repump / Zeeman light switches li_cooling_power / li_repump_power / li_zeeman_power power of the individual beams li_lock_mot / li_lock_cmot frequency-lock references Parameters (build excerpt) MOT_Axial / _Radial, CMOT_Axial / _Radial (gradient/homogeneous-field currents), MOT_Current / CMOT_Current (trap currents), MOT_detuning / CMOT_detuning (detunings).https://www.quatm.com/en/docs/examples/ultracold-atoms/absorption-imaging/Mon, 01 Jan 0001 00:00:00 +0000https://www.quatm.com/en/docs/examples/ultracold-atoms/absorption-imaging/Overview This experiment script provides the class absorption_imaging: build() declares the cooling/imaging light and the camera trigger and exposes the MOT loading, the probe flash and the free-flight expansion time as parameters; run() orchestrates the imaging sequence and provides two detection modes, fluorescence_imaging and absorption_imaging. Parameters (build excerpt) Mot_loading, Flash_us (duration of the probe flash), expansiontime_ms (free-flight expansion), image_detuning (imaging detuning), MOT_detuning. Devices (build excerpt) li_cooling_aom / li_repump_aom / li_zeeman_aom (cooling/repump/Zeeman), li_absorption_h (horizontal absorption probe beam), li_imaging_valon + dds_0 (imaging frequency source), trigger_radba (trigger).https://www.quatm.com/en/docs/examples/atom-ion-interaction/atomion-interaction-in-an-optical-dipole-trap/Mon, 01 Jan 0001 00:00:00 +0000https://www.quatm.com/en/docs/examples/atom-ion-interaction/atomion-interaction-in-an-optical-dipole-trap/Overview In this example we combine a lithium MOT / optical dipole trap (ODT) with the cooling, shuttling and state detection of a barium ion into one complete atom–ion interaction experiment. The experiment class interaction_optical_trapping subclasses Experiment, and the main sequence is assembled in stages by methods such as init_CMOT, absorption_imaging, expose_camera and run. A typical sequence is roughly: load the MOT and pre-cool the ion and shuttle it “out of the way”, then load the atom cloud into the CMOT and the optical dipole trap, and after evaporation and spin polarisation move the ion back and let it interact with the atoms (loss spectroscopy or Feshbach resonance measurements are possible); finally perform optical thermometry, absorption imaging and detection of the ionic product state.https://www.quatm.com/en/docs/examples/ion-trap-experiments/quantum-state-manipulation-and-detection/Mon, 01 Jan 0001 00:00:00 +0000https://www.quatm.com/en/docs/examples/ion-trap-experiments/quantum-state-manipulation-and-detection/Overview This experiment script provides the class state_prep: it optically pumps the ion into the S1/2 or D3/2 state and can optionally apply one more cooling cycle at the end. State-dependent detection then distinguishes the bright/dark states by fluorescence counting. Parameters on_s_off_d (pump to S1/2 (650 off) or to D3/2 (493 off)), cooling_end (whether to add one cooling step before the end). State-preparation logic S1/2: switch off the 650 light first → the ion falls into S1/2; D3/2: switch off the 493 light first → the ion is pumped into D3/2.https://www.quatm.com/en/docs/examples/ultracold-atoms/optical-dipole-trap-experiment/Mon, 01 Jan 0001 00:00:00 +0000https://www.quatm.com/en/docs/examples/ultracold-atoms/optical-dipole-trap-experiment/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.https://www.quatm.com/en/docs/examples/ion-trap-experiments/optically-trapped-ion/Mon, 01 Jan 0001 00:00:00 +0000https://www.quatm.com/en/docs/examples/ion-trap-experiments/optically-trapped-ion/Overview This example uses the experiment class OpticalTrappingIon to demonstrate purely optical trapping of a single ion in an optical dipole trap. The radio-frequency trap (rf) can optionally be switched off in order to measure the performance of the pure optical trap, and optical trapping can also be performed in an adjustable magnetic field; together with ion laser cooling, spin preparation and product-state detection, the ion can also be moved into and out of the trap via the axial electrodes.