Observation of the Berezinskii-Kosterlitz-Thouless Transition in a Two-Dimensional Bose Gas via Matter-Wave Interferometry

Autor:	Sunami, S, Singh, VP, Garrick, D, Beregi, A, Barker, AJ, Luksch, K, Bentine, E, Mathey, L, Foot, CJ
Rok vydání:	2022
Předmět:	General Physics and Astronomy
Zdroj:	Physical Review Letters. 128
ISSN:	1079-7114 0031-9007
DOI:	10.1103/physrevlett.128.250402
Popis:	We probe local phase fluctuations of trapped two-dimensional (2D) Bose gases using matter-wave interferometry. This enables us to measure the phase correlation function, which changes from an algebraic to an exponential decay when the system crosses the Berezinskii-Kosterlitz-Thouless (BKT) transition. We determine the temperature dependence of the BKT exponent η and find the critical value ηc = 0.17(3) for our trapped system. Furthermore, we measure the local vortex density as a function of the local phase-space density, which shows a scale-invariant behaviour across the transition. Our experimental investigation is supported by Monte Carlo simulations and provides a comprehensive understanding of the BKT transition in a trapped system.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_dedup___::e5ec1179b9c9bea2ba6dfd678dc8ba94 https://doi.org/10.1103/physrevlett.128.250402 Zobrazit plný text záznamu