Speaker: Dr Matt Reeves
Affiliation: University of Queensland


Ultracold atom experiments allow unprecedented  control over the dynamics of  quantum systems. Developments such as arbitrary optical potential generation and single-site addressing schemes in optical lattices have generated an increased interest in the development of so-called ‘atomtronic’ devices. Such devices aim to develop circuits or sensors that leverage quantum aspects such as quantum coherence or superfluid transport.In atomtronic tunnelling junctions, experiments have observed desirable nonlinear features that are routinely harnessed in traditional semiconductor electronics circuits, including nonequilibrium bistability [1] and negative differential conductivity [2]. However, the nonequilibrium dynamics of these quantum systems poses a challenge for theory, and a cohesive theoretical model which can capture the observed behaviours has not yet been developed.In this talk I will present a theoretical model we have developed to describe the bosonic tunnelling junctions using classical field methods [3]. In contrast to previously developed single-mode approximations, the classical field method is found to quantitatively describe many of the observed tunnelling phenomena, without the need for fitting parameters. Our multimode model suggests the nonequilbrium condensate dynamics occurring locally at each junction site hold several important implications for atomtronic applications and the interpretation of particle transport phenomena.

[1] R Labouvie et al., Phys. Rev. Lett. 115, 050601 (2015)
[2] R. Labouvie et al., Phys. Rev. Lett. 116, 235302(2016)
[3] M. T. Reeves and M. J. Davis, arXiv:2102.02949 (2021)

About Australia - New Zealand Cold Atom Seminars

This new initiative hosts a seminar once a month for the Australia – New Zealand cold atom research community.  The purpose is to encourage and facilitate ongoing discussions and collaboration in the local community.  Talks should be less than 40 minutes in length to allow ample time for questions and discussion.

Seminars will be held on the last Friday of the month (except for December) at 1pm Melbourne time (which is normally 3pm New Zealand time).  While the primary format is online via Zoom, various institutions will host the seminar in local seminar rooms.  The Zoom link is https://uqz.zoom.us/j/88604569495

You can sign up for announcements for the seminars at this webpage:

Seminars are recorded, and past seminars can be accessed from this web page.

Contact Matthew Davis mdavis@physics.uq.edu.au for further information.



Physics Annexe (06)
Room: 407 (and via Zoom: