Chiral Anomaly and Temperature Effects in Tilted Doped Weyl Semi-metals: Dichroism And Dynamic Hall Angle

We calculate the absorptive part of the dynamic conductivity for both right and left handed circular polarized light in the Kubo formalism. Due to finite contribution from the imaginary part of Hall conductivity, we observe dichroism in certain frequency regime. Including the effect of chiral pumping creates difference in chemical potential in the positive and negative chirality nodes, which leads to additional regions of frequencies where dichroism remains finite. We have also considered the case of a non-centrosymmetric Weyl semi-metal in which the two nodes are displaced in energy by an amount ±Q₀. This also modifies the dichroism in a similar fashion. Further, with increase in temperature (T), the boundaries of the regions of finite dichroism become smeared out in energy and extend beyond their original range for T = 0 and at the same time the dichroism is reduced. When T is increased to be of the order of the chemical potential associated with the doping, the dichroism vanishes. We have also extended the work to include the frequency variation of dynamic Hall angle for both zero and finite temperature cases.