Magnus expansion applied to a dissipative driven two-level system

• Main Authors: Tuguldur Kh. Begzjav, Hichem Eleuch
• Format: Article
• Language: English
• Published: Elsevier 2020-06-01
• Series: Results in Physics
• Subjects: Magnus expansion; Two-level system; Dissipative system
• Online Access: http://www.sciencedirect.com/science/article/pii/S2211379720307567

One of the most powerful and potentially useful methods of time-dependent matrix differential equations is the Magnus expansion. In this work, we applied the Magnus expansion for Schrödinger and master equations of a dissipative two-level system interacting with a time-dependent π pulse. Two different models of dissipative two-level systems are considered, namely (i) the system decays from two considered levels into some other levels with given decay rates; (ii) the system decays from its excited level to its ground level. The obtained approximate solutions of a time dynamics by the first-order Magnus expansion are well consistent with the results of numerical calculations obtained by the fourth-order Runge-Kutta method.