FINESS2024: FInite temperature Non-Equilibrium Superfluid Systems

Phononic crystal trapping geometries for improved rotational sensing with ultracold atoms

4 Sept 2024, 17:00

2h

Wavebreak & Miami room

Poster FINESS Posters II

Speaker

Lachlan Miller

Description

Ultracold atom interferometry for inertial sensing in GPS/GNSS-denied environments presents a compact and more sensitive alternative to traditional methods such as light interferometry. While free-space interferometers have approached commercial scale implementation, trapping the atomic sample throughout the measurement may offer greater robustness to accelerations of the apparatus, although it is potentially limited by increased phase-diffusion due to two-body interactions at high densities.

Marti et al. [1] developed a sensor that measured rotation using the interference of counterpropagating standing-wave phonons in a ring geometry. Building on this work, we recently explored the sensing limits of this trapped atom system, experimentally finding an improved sensitivity of 0.3 rad s$^{-1}$. Numerical modelling found that higher harmonic generation by phonon mode mixing and thermal damping limit the lifetime of the imprinted phonons and the Q value [2].

To address this issue, we explore the implementation of a resonant phononic crystal geometry, extending our findings with atomtronic Helmholtz resonators [3]. We simulate the evolution of the system in this new geometry with the Gross-Pitaevski Equation, investigating the role of geometry on the lifetime of imprinted phonons and hence the theoretical Q value. Experimentally, confining the atoms to novel 2D geometries and limiting the thermal background may improve the sensitivity of the rotational sensor.

References

1. G. E. Marti, R. Olf and D. M. Stamper-Kurn, Collective excitation interferome- try with a toroidal Bose-Einstein condensate, Phys. Rev. A 91, 013602 (2015), doi:10.1103/PhysRevA.91.013602.
2. C. W. Woffinden, A. J. Groszek, G. Gauthier, B. J. Mommers, M. W. J. Bromley, S. A. Haine, H. Rubinsztein-Dunlop, M. J. Davis, T. W. Neely and M. Baker, Viability of rotation sensing using phonon interferometry in Bose-Einstein condensates, SciPost Phys. 15, 128 (2023), doi: 10.21468/SciPostPhys.15.4.128
3. G. Gauthier, S. S. Szigeti, M. T. Reeves, M. Baker, T. A. Bell, H. Rubinsztein-Dunlop, M. J. Davis and T. W. Neely, Quantitative Acoustic Modes for Superfluid Circuits, Phys. Rev. Lett. 123, 260402 (2019), doi: 10.1103/PhysRevLett.123.260402

Short bio (50 words) or link to website

https://www.uq-bec.org/lachlan-miller-1