Frequency and orientation dependent conductivity of a semi-Dirac system

The intra- and interband optical conductivities of a semi-Dirac system are determined. It was found that the conductivity in the linear direction is considerably stronger than the conductivity in the parabolic direction. For an electrical field applied along a non-principal axis, both the the longitudinal and transverse current are nonzero. Due to the anisotropy of the system, the transverse conductivity for an oblique applied field can exceed the longitudinal conductivity.