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Efficiency of different numerical methods for solving Redfield equations

Ivan Kondov·Ulrich Kleinekathoefer·Michael Schreiber
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Abstract

The numerical efficiency of different schemes for solving the Liouville-von Neumann equation within multilevel Redfield theory has been studied. Among the tested algorithms are the well-known Runge-Kutta scheme in two different implementations as well as methods especially developed for time propagation: the Short Iterative Arnoldi, Chebyshev and Newtonian propagators. In addition, an implementation of a symplectic integrator has been studied. For a simple example of a two-center electron transfer system we discuss some aspects of the efficiency of these methods to integrate the equations of motion. Overall for time-independent potentials the Newtonian method is recommended. For time-dependent potentials implementations of the Runge-Kutta algorithm are very efficient.

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Ivan Kondov, Ulrich Kleinekathoefer, Michael Schreiber. 2000-09-16. Efficiency of different numerical methods for solving Redfield equations. https://doi.org/10.1063/1.1335656

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