17 research outputs found
Data for "Interferometric laser cooling of atomic rubidium"
Dataset supports: Dunning, A. et al. (2015). Interferometric laser cooling of atomic rubidium. Physical Review Letters, 115(73004), 1-5. </span
Dataset for Velocimetry of cold atoms by matter-wave interferometry
Paper relates to the measurement of the velocity distribution of atoms within a laser-cooled sample by the means of atom interferometry, by employing an asymmetric Mach-Zehnder interferometer.
Data are attached for interferometer output used in 3 velocity profile measurements, with corresponding Raman Doppler spectroscopic measurements of the profiles for comparison.
The first column of each data file is the parameter varied, either the temporal asymmetry of the interferometer (in ns) for the interferometer data, or the laser detuning (in kHz) for the spectroscopic measurements.
The "output" columns are measurements of the fraction of atoms in the upper energy state. If multiple data are taken for a single point, more that one "output" column is present and additional columns are included for the mean and standard deviation. When there is only one output column, the uncertainty in the measurement of the excited state population is given.
Data files with the "doppler-" prefix are the spectroscopic measurements, while each interferometer measurement has two data files taken with ("-inphase" suffix) and without ("-quadrature" suffix) a pi/2 phase shift prior to the final interferometer pulse.
The numerical suffix links spectroscopic and interferometric measurements taken under the same conditions.
Correction: One of the previously listed co-creators, David Elcock, requested that his name be removed from the creator list, which has been implemented. (2021-10-28)</span
Optimal control of mirror pulses for cold-atom interferometry
Atom matterwave interferometry requires mirror and beamsplitter pulses that are robust to inhomogeneities in field intensity, magnetic environment, atom velocity and Zeeman sub-state. We present theoretical results which show that pulse shapes determined using quantum control methods can significantly improve interferometer performance by allowing broader atom distributions, larger interferometer areas and higher contrast. We have applied gradient ascent pulse engineering (GRAPE) to optimise the design of phase-modulated mirror pulses for a Mach-Zehnder light-pulse atom interferometer, with the aim of increasing fringe contrast when averaged over atoms with an experimentally relevant range of velocities, beam intensities, and Zeeman states. Pulses were found to be highly robust to variations in detuning and coupling strength, and offer a clear improvement in robustness over the best established composite pulses. The peak mirror fidelity in a cloud of ∼ 80 µK 85Rb atoms is predicted to be improved by a factor of 2 compared with standard rectangular π pulses