Tanawut NoungneawSujin SuwannaAreeya ChantasriGriffith UniversityMahidol University2022-08-042022-08-042021-01-28Journal of Physics: Conference Series. Vol.1719, No.1 (2021)17426596174265882-s2.0-85100794203https://repository.li.mahidol.ac.th/handle/20.500.14594/79015In this work, the Stratonovich stochastic differential equation is considered in the derivation of the maximum a posteriori path (MAP) for an open quantum system. We have derived the modified Onsager-Machlup (OM) function for a stochastic process, which plays an analogous role of the Lagrangian in the conventional classical mechanics. Variational method is applied to obtain the Euler-Lagrange equations. We show that the MAP trajectory is close to the quantum most-likely path obtained by Chantasri et al. [1], but in general not exactly the same. For an open quantum system subject to a no-knowledge measurement, both methods produce the same most-likely path. Numerical simulations for both the modified OM and the quantum most-likely path methods agree very well with theoretical predictions, regardless of the evolution time and different post-selected states.Mahidol UniversityPhysics and AstronomyConference PaperSCOPUS10.1088/1742-6596/1719/1/012101