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arXiv · 2007.05308

Fourth-order leapfrog algorithms for numerical time evolution of classical and quantum systems

Jun Hao Hue·Ege Eren·Shao Hen Chiew·Jonathan Wei Zhong Lau·Leo Chang·Thanh Tri Chau·Martin-Isbjörn Trappe·Berthold-Georg Englert
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Abstract

Chau et al. [New J. Phys. 20, 073003 (2018)] presented a new and straight-forward derivation of a fourth-order approximation '$U_7$' of the time-evolution operator and hinted at its potential value as a symplectic integrator. $U_7$ is based on the Suzuki-Trotter split-operator method and leads to an algorithm for numerical time propagation that is superior to established methods. We benchmark the performance of $U_7$ and other algorithms, including a Runge-Kutta method and another recently developed Suzuki-Trotter-based scheme, that are exact up to fourth order in the evolution parameter, against various classical and quantum systems. We find $U_7$ to deliver any given target accuracy with the lowest computational cost, across all systems and algorithms tested here. This study is accompanied by open-source numerical software that we hope will prove valuable in the classroom.

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Jun Hao Hue, Ege Eren, Shao Hen Chiew, Jonathan Wei Zhong Lau, Leo Chang, Thanh Tri Chau, Martin-Isbjörn Trappe, Berthold-Georg Englert. 2020-07-10. Fourth-order leapfrog algorithms for numerical time evolution of classical and quantum systems. https://arxiv.org/abs/2007.05308

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