Abstract: In right-handed material, the group velocity and the energy are in the same way of electromagnetic wave, the phase velocity and the group velocity desires of the Rayleigh relation of electromagnetic wave. In this paper, in order to study the electromagnetic properties of left-handed material, the phase velocity, the group velocity and relation each other of electromagnetic wave in left-handed material is proved theoretically, and to a conclusion negative group velocity of electromagnetic wave. The application of left-handed material is introduced.

Key words: left-handed material, phase velocity, group velocity, negative direction energy spreading