Conveners
AIP: Atomic and Molecular Physics: ATMOP 1 - Open systems & topology
- Matthew Davis (The University of Queensland)
AIP: Atomic and Molecular Physics: ATMOP 2 - Superfluidity & vortex lattices
- Sean Hodgman
AIP: Atomic and Molecular Physics: ATMOP 3 - Atomic clocks
- Jacinda Ginges
AIP: Atomic and Molecular Physics: ATMOP 4 - Spin physics/correlations
- Andy Martin
AIP: Atomic and Molecular Physics: ATMOP 5 - New physics in precision atomic experiments
- Igor Bray (Curtin University)
AIP: Atomic and Molecular Physics: ATMOP 6 - Condensate dynamics
- Brendan Mulkerin
AIP: Atomic and Molecular Physics: ATMOP 7 - Atom/molecule-light interactions
- Robert Sang (Griffith University)
AIP: Atomic and Molecular Physics: ATMOP 8 - Session in honour of Michael Brunger
- Stephen Buckman (Australian National University)
In this work, we experimentally create a lattice of vortices in a two-dimensional BEC and map the vortex density as the lattice melts. These states have gained prominence as an analogue of electrons in the quantum hall effect.
We demonstrate the laser cooling techniques for rapid production of a metastable helium BEC. The experimental setup features an in-vacuum magnetic trap and a cross-beam optical dipole trap. We obtained a pure BEC of 1 million atoms in 3.3 seconds.
We present our experimental progress towards demonstrating quantum non-locality in a matter wave system of ultracold helium via a Rarity-Tapster interferometer. The momentum entangled state used for the violation is generated by colliding helium Bose-Einstein condensates.
We propose a new, low-loss method of cooling neutral alkali atoms to quantum degeneracy by optical feedback control. We present full-field quantum simulations demonstrating the viability of the technique, and show robustness to realistic experimental imperfections.
This is theoretical work on quantised vortices in superfluids with a specific focus on connections between the theory of rotating neutral superfluids, topological quantum computation, and gravitation endowed by an acoustic metric.
We present a microscopic theory of thermally-damped vortex motion in oblate atomic superfluids, providing a microscopic origin for the damping and Brownian motion of quantized vortices in two-dimensional atomic superfluids, which has previously been limited to phenomenology.
When subjected to a rotating magnetic field, the resulting precession of the dipole moments of a dipolar BEC imparts angular momentum to the system. We show how this can be used to generate vortex lattices, as observed in recent experiments.
We apply machine learning methods to control and optimise the stirring protocol imposed on Rubidium-87 Bose-Einstein condensates in experiment. The optimisation allows for controlled generation of various persistent current states albeit with no universal optimum stirring parameters.
We study the behaviour of drag in superfluids and observe the universal relation between the Reynolds number and drag coefficient in superflow. This establishes hydrodynamic scale invariance extends into the limit of quantum fluids.
Optical atomic clocks combined with the proliferation of compact optical frequency combs, offer higher inherent timing stability versus their current microwave counterparts. We detail the development and demonstrations of our portable optical atomic clock technology with bespoke comb outside the laboratory under rugged conditions, and outline future directions.
- Study metastable excited states for these ions as clock transitions in optical clocks.
- Calculating several atomic properties.
- CI+SD and CIPT methods are used.
- Black body radiation (BBR) found 10^-16-10^-18.
- The enhancement coefficient reached K= 8.3.
We investigate excitation of atoms using extremely short pulses of light with intensities above $10^{14}$ W/cm$^2$. The carrier-envelope-phase of the pulse modifies the interaction and marks a change in the dynamics.
Radioactive Noble Gas isotopes are ideal tracers of environmental processes. Due to their low abundances, a lack of measurements is a limitation in climate modelling. We present progress towards an Atom Trap Trace Analysis (ATTA) facility for overcoming this limitation.
We investigate the nonlinear response of heavy impurity in ultracold Fermi gases and superfluid with a numerically exact approach. Our results are highly relevant for polaron physics.
We investigate quantum spin systems realised in a dilute gas of ultracold polar molecules pinned in a deep optical lattice. We discuss a novel disorder mechanism for engineering many-body localisation, and explore the system's non-equilibrium dynamics in one and two-dimensions.
We explore finite-temperature phases of a spin-1 ferromagnetic Bose gas, identifying mass and spin BKT transitions, a vortex plasma phase, and novel critical scaling of spatial correlations.
Ultradilute Quantum Droplets
Reporting on several of our recent works on the hyperfine anomaly and its importance in searches for new physics in precision atomic experiments.
We have used a combination of muonic-atom and atomic many-body calculations to extract magnetic hyperfine anomaly in caesium atom from muonic cesium measurements. Our result is important for cesium atomic parity violation studies.
Presentation of atomic excitation factors and calculated event rates for DM-electron scattering, and how they compare to the excess seen in the XENON1T experiment.
This presentation will cover a number of atomic energy level measurements involving ultracold metastable helium atoms, including using a tuneout wavelength to probe atomic QED theory.
Total cross sections for all single-electron processes in proton scattering on molecular hydrogen have been calculated within a two-centre coupled-channel approach, providing improved agreement between theory and experiment for this challenging collisional system.
We study the dynamics in a strongly interacting Fermi gas following a quench of the interactions. Using two-photon Bragg spectroscopy, we directly observe the amplitude oscillations, obtaining measurements of the pairing gap and damping rate as a function of temperature.
We theoretically investigate breading oscillations of a harmonically trapped 1D quasicondensate at finite temperatures. We find that the oscillations exhibit beating of two oscillatory modes, unlike previous studies that predicted only a single oscillation frequency.
To study the viability of a rotation sensing scheme using ultracold atoms, we numerically model the decay of standing waves excited in the density of a ring-shaped Bose-Einstein condensate.
We briefly review the research on second sound in ultracold atomic physics, with emphasis on strongly interacting unitary Fermi gases with infinitely large s-wave scattering length.
We consider a quasi-one-dimensional dipolar BEC, with strong trapping along the two-axis orthogonal to the aligning dipole field (z-axis). When the z-axis trapping is switched off we numerically and analytically characterise the frequency and amplitude of the BEC width oscillations.
We present precise measurement of HHG phase difference between two isotopes of molecular hydrogen using advanced Gouy phase interferometer. The measured phase difference is about 200 mrad, corresponding to ~3 attoseconds time delay which is nearly independent of harmonic order.
Investigations in to satellite lines and diagram lines of complex open shell 3d transition metals. Specifically in scandium for this talk.
A novel technique for determining complex atomic fine structure will be described. Exciting applications of the technique such as a phase analogue to x-ray absorption fine structure applications will also be discussed.
We demonstrate an accurate phase retrieval of XUV atomic ionization by streaking photoelectrons in a circularly polarized IR laser field. This novel technique will be instrumental for studying inner shell atomic and molecular ionization using free-electron lasers.
High Energy Resolution Fluorescence Detection has recently developed as a powerful probe for bonding, nanostructure and oxidation state. We report the discovery of a new satellite in manganese using a new technique, XR-HERFD. This is foundational for many future studies.
A method for computational modeling of electron interactions in gases is applied to processes in the Earth’s mesosphere. Electrons in different subranges of energy are treated in the same way as species in chemical models.
Submission for oral presentation
We will present a novel method to determine the polarization state of a positron beam via interaction with a spin-polarized target to produce positronium atoms and discuss the theoretical limit on its analysing power.
Calculation of antihydrogen formation via excited positronium (Ps($nl$), $n\le7$) scattering on antiprotons is presented using the convergent close-coupling and classical trajectory Monte Carlo approaches. Though there are substantial disagreement for $n\le2$, we obtain good agreement for $n\ge3$.
We have extended the single-centre CCC to allow application to atoms with any number of electrons. We have addressed deficits in this method using a complex model potential calculation. Using this new approach we have completed positron carbon scattering calculations.
We report on recent progress in applications of the convergent close-coupling approach to ion-atom collisions. The approach allows one to take into account all underlying processes of excitation, ionisation, and electron capture into bound and continuum states of the projectile.
