Strong birefringence in left-handed metallic metamaterials

We present a layout for the construction of strongly birefringent left-handed metamaterials in the THz domain. Using finite integration technique simulations, we show that the strength of the birefringence can be controlled by tuning the geometrical parameters of the structure. The difference of the effective refractive indices for ordinary and extraordinary propagation can reach very high values, so the maximum calculated index difference is found to be 0.727. Utilizing the presented approach with a properly chosen set of parameters allows for the construction of a very compact left-handed quarter wave plate with a geometrical thickness smaller than the operating wavelength.