Observation of negative refraction in the graphene/ferrite composite

An observation of negative refraction in the naturally obtained composition of graphene and barium ferrite is reported. The capacitance and inductance measurements revealed the electric and magnetic resonances accompanied with the negative values of permittivity and permeability in the overlapped frequency range. According to the “left‐handed” media approach such a material is characterized by negative refraction. The derived values of the real part of refractive index are negative at the frequencies above 500 MHz. (© 2014 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim) The graphene/barium ferrite composite reveals the electric and magnetic resonances accompanied with negative values of permittivity and permeability in the overlapped frequency range. As a result this material shows negative refraction at frequencies above 500 MHz.