Efficient time integration methods for Gross-Pitaevskii equations with rotation term

[EN] The objective of this work is the introduction and investigation of favourable time integration methods for the Gross-Pitaevskii equation with rotation term. Employing a reformulation in rotating Lagrangian coordinates, the equation takes the form of a nonlinear Schrödinger equation involving a space-time-dependent potential. A natural approach that combines commutator-free quasi-Magnus exponential integrators with operator splitting methods and Fourier spectral space discretisations is proposed. Furthermore, the special structure of the Hamilton operator permits the design of specifically tailored schemes. Numerical experiments confirm the good performance of the resulting exponential integrators.Part of this work was developed during a research stay at the Wolfgang Pauli Institute Vienna; the authors are grateful to the director Norbert Mauser and the staff members for their support and hospitality. Philipp Bader, Sergio Blanes, and Fernando Casas acknowledge funding by the Ministerio de Economía y Competitividad (Spain) through project MTM2016-77660-P (AEI/FEDER, UE).Bader, P.; Blanes Zamora, S.; Casas, F.; Thalhammer, M. (2019). Efficient time integration methods for Gross-Pitaevskii equations with rotation term. Journal of Computational Dynamics (Online). 6(2):147-169. https://doi.org/10.3934/jcd.2019008S1471696

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