On The Left-Handed Ferrite Waveguide

The left-handed (LH) materials are very active subject with increasing interests for microwave engineers. The polycrystalline YIG slab of thickness d is inserted into the center of the rectangular waveguide under cutoff frequency and magnetized transversely to wave propagation by mu₀H₀. Dispersion relation of the waveguide is calculated from Maxwellpsilas equation and boundary conditions assuming TE_n0 mode. The effect of magnetic loss factor for LH surface mode is also estimated using perturbation approach, which is significant for attenuation of wave propagation. Wire antenna at input port is taken for excitation of TE₁₀ mode. Frequency response from LH surface mode is measured by network analyzer. Small peak response of bandwidth of few tenth MHz at 2.9 GHZ for polycrystalline TIG is observed with insertion loss of more than 20 dB, which will be tuned by magnetic field.