Dynamics of ultracold atoms near microstructures

In this talk I will consider the mutual interaction between ultracold atom clouds and nearby quantum electronic structures. In particular I will consider the potential advantages of using quantum electronic components to trap, manipulate, and electrically image ultracold atoms. Conversely, I will also consider how the cold atom clouds can be used to provide functional imaging of the electronic systems.

I will present calculations which predict that current through quantum electronic components fabricated within a two-dimensional electron gas (2DEG) in semiconductor heterostructures [1] and graphene multilayers [2,3] can trap ultracold atoms ~200 nm away, with orders of magnitude less spatial and temporal noise than for metal trapping wires. This noise reduction, combined with low Casimir-Polder attraction [2], may enable the creation of hybrid atom chip structures, which exploit small changes in the conductance of quantum electronic devices to control the trapped atoms. For example, activating a single quantized conductance channel in a quantum point contact can split a Bose-Einstein (BEC) for atom interferometry [1,4]. In turn, the response of the BEC to the opening and closure of conduction channels offers a route to functional imaging of quantum devices and transport.

[1] G. Sinuco-León, B. Kaczmarek, P. Krüger, and T.M. Fromhold, Phys. Rev. A 83, 021401(R) (2011).

[2] T.E. Judd, R.G. Scott, A.M. Martin, B. Kaczmarek and T.M. Fromhold, New J. Phys. 13, 083020 (2011).

[3] L. Britnell et al., Nature Commun. 4, 1794 (2013).

[4] T.W.A. Montgomery, W. Li and T.M. Fromhold, Phys. Rev. Lett. 111, 105302 (2013).