Reversed Cherenkov radiation in a waveguide filled with anisotropic double-negative metamaterials

The physical properties of Cherenkov radiation (CR) are theoretically investigated for a charged particle traveling along the axis of a cylindrical waveguide filled with anisotropic double-negative metamaterials (DNMs). The reversed CR and CR conditions are obtained using analytical method. The influence of the particle velocity, the waveguide radius, and the constitutive parameters of the anisotropic DNMs are discussed. A numerical example illustrates that the total radiated energy increases with increasing particle velocity, the radiated energy spectral density has different poles at the different frequencies for different anisotropic DNMs when the loss of the anisotropic DNM is smaller, and when the radius has the same order as the operating wavelength, the influence of the waveguide radius on the total radiated energy is smaller on the whole. Since most of the metamaterials realized so far are anisotropic, our theoretical work based on anisotropic DNMs will be helpful for future experimental realizations. (c) 2008 American Institute of Physics.