In this work, we shall demonstrate that timeaveraged stored energy density (TASED) of a circularly polarized wave is equal to zero, in addition, TASEDs of both circularly and linearly polarized waves do not directly relate to their time-averaged Poynting vector (TAPV), respectively, which indicates that the usual definition of energy flow velocity needs to be reconsidered. Noting that energy U of electromagnetic wave (photon) obtained from relativistic energy-momentum relation corresponds to transport of electromagnetic energy, combining expressions of both TAPV and time-averaged electromagnetic wave momentum density, a new definition of energy flow velocity is proposed by applying energy U instead of TASED. Furthermore, we shall show from the new definition that a rational energy flow velocity of electromagnetic wave traveling in a material medium is obtained by adopting Minkowski electromagnetic wave momentum density, which may provide a new way to further discuss the long-standing Abraham-Minkowski controversy.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.