Material equations and Maxwell equations for isotropic media; waves with negative group velocity and negative values of ε (ω) and μ (ω)
A.A. Rukhadzea,b aProkhorov General Physics Institute of the Russian Academy of Sciences, ul. Vavilova 38, Moscow, 119942, Russian Federation bMoscow Institute of Physics and Technology (National Research University), Institutskii per. 9, Dolgoprudny, Moscow Region, 141701, Russian Federation cBauman Moscow State Technical University, ul. 2-ya Baumanskaya 5/1, Moscow, 105005, Russian Federation
The frequently used Maxwell equations that contain E, B, D and H fields are only substantiated in the framework of linear material equations and for isotropic media alone. We have shown that the account of the deviation of magnetic permittivity $\mu(\omega)$ verse waves only exist in the energy region where $\epsilon(\omega)$ and have a positive group velocity.
Keywords: conductivity tensor, dielectric permittivity tensor, isotropic media, electric and magnetic permittivity, phase and group velocity of transverse electromagnetic wave PACS:03.50.De, 41.20.Jb (all) DOI:10.3367/UFNe.2019.01.038522 URL: https://ufn.ru/en/articles/2019/5/d/ Citation: Makarov V P, Rukhadze A A "Material equations and Maxwell equations for isotropic media; waves with negative group velocity and negative values of ε (ω) and μ (ω)" Phys. Usp.62 487–495 (2019)