What are the left-handed media and what is interesting about them?
Chto takoe levye sredy i chem oni interesny?

Konstantin Yu. Bliokh, Yurii P. Bliokh
2004 Uspehi fiziceskih nauk  
We review the intensively discussed ideas about wave propagation and refraction in media where both electric permittivity and magnetic permeability are negative. The criticism against negative refraction as violating the causality principle is considered. Starting from the initial wave equations, refraction of beams at the boundary of a lefthanded medium is analyzed. The physics of a perfect lens formed by a flat layer of a left-handed material is considered.
doi:10.3367/ufnr.0174.200404j.0439 fatcat:bg4jk7kghzekng3ewdlh7mapta