High Sensitivity MultiAxes Rotation Sensing Using Large Momentum Transfer Point Source Atom Interferometry
Abstract
A point source interferometer (PSI) is a device where atoms are split and recombined by applying a temporal sequence of Raman pulses during the expansion of a cloud of cold atoms behaving approximately as a point source. The PSI can work as a sensitive multiaxes gyroscope that can automatically filter out the signal from accelerations. The phase shift arising from rotations is proportional to the momentum transferred to each atom from the Raman pulses. Therefore, by increasing the momentum transfer, it should be possibly to enhance the sensitivity of the PSI. Here, we investigate the degree of enhancement in sensitivity that could be achieved by augmenting the PSI with large momentum transfer (LMT) employing a sequence of many Raman pulses with alternating directions. Contrary to typical approaches used for describing a PSI, we employ a model under which the motion of the center of mass of each atom is described quantum mechanically. We show how increasing Doppler shifts lead to imperfections, thereby limiting the visibility of the signal fringes, and identify ways to suppress this effect by increasing the effective, twophoton Rabi frequencies of the Raman pulses. Taking into account the effect of spontaneous emission, we show that, for a given value of the onephoton Rabi frequency, there is an optimum value for the number of pulses employed, beyond which the net enhancement in sensitivity begins to decrease. For a onephoton Rabi frequency of 200 MHz, for example, the peak value of the factor of enhancement in sensitivity is ~39, for a momentum transfer that is ~69 times as large as that for a conventional PSI. We also find that this peak value scales as the onephoton Rabi frequency to the power of 4/5.
 Publication:

Atoms
 Pub Date:
 August 2021
 DOI:
 10.3390/atoms9030051
 arXiv:
 arXiv:2006.13442
 Bibcode:
 2021Atoms...9...51L
 Keywords:

 Quantum Physics