Coherence and linewidth of a continuously pumped atom laser at finite temperature

Abstract

(2015) Coherence and linewidth of a continuously pumped atom laser at finite temperature. Physical Review A, 92 (1). p. 3605. ISSN 10503605. ISSN -2947 This version is available from Sussex Research Online: http://sro.sussex.ac.uk/66132/ This document is made available in accordance with publisher policies and may differ from the published version or from the version of record. If you wish to cite this item you are advised to consult the publisher's version. Please see the URL above for details on accessing the published version. Copyright and reuse:Sussex Research Online is a digital repository of the research output of the University.Copyright and all moral rights to the version of the paper presented here belong to the individual author(s) and/or other copyright owners. To the extent reasonable and practicable, the material made available in SRO has been checked for eligibility before being made available.Copies of full text items generally can be reproduced, displayed or performed and given to third parties in any format or medium for personal research or study, educational, or not-for-profit purposes without prior permission or charge, provided that the authors, title and full bibliographic details are credited, a hyperlink and/or URL is given for the original metadata page and the content is not changed in any way.PHYSICAL REVIEW A 92, 013605 (2015) Coherence and linewidth of a continuously pumped atom laser at finite temperature A continuous-wave atom laser formed by the outcoupling of atoms from a trapped Bose-Einstein condensate (BEC) potentially has a range of metrological applications. However, in order for the device to be truly continuous, a mechanism to replenish the atoms in the BEC is required. Here we calculate the temporal coherence properties of a continuously pumped atom laser beam outcoupled from a trapped Bose-Einstein condensate that is replenished from a reservoir at finite temperature. We find that the thermal fluctuations of the condensate can significantly decrease the temporal coherence of the output beam due to atomic interactions between the trapped BEC and the beam, and this can impact the metrological usefulness of the device. We demonstrate that a Raman outcoupling scheme imparting a sufficient momentum kick to the atom laser beam can lead to a significantly reduced linewidth.

Space continuous atom laser in one dimension

“…That is to say, we have ne-glected the temperature effect and quantum fluctuations. [65][66][67] Density fluctuations and phase fluctuations due to collisions between condensate and high energy lying atoms at finite temperature will be considered in the future studies. For the truly continuous atom laser, the repumping mechanism should be considered, [66,68,69] which will be done in future studies.…”

Catastrophe Atom Optics: Fold and Cusp Caustics in an Atom Laser

“…Caustics formed by atomic trajectories have previously been discussed in specific settings, for example in the context of atoms being released from a magneto-optical trap [24,25], atoms diffracting from a one-dimensional optical lattice [26,27], or expanding Bose-Einstein condensates (becs) with spatially varying initial phase [28]. However, for the study of caustics, a particularly powerful tool and natural setting is an atom laser [29][30][31][32][33][34][35][36][37][38][39][40][41][42], which is a coherent stream of atoms that is out-coupled from a dilute-gas bec. In contrast to the studies above, the use of a collimated atom laser in our experiments provides a generic setting for studying a broad variety of catastrophe features, including the direct imaging of sharply delineated features and a wealth of observable phenomena dependent on the shape, strength, and sign of the potential.…”