Dirac cones produces negative interlayer magnetoresistance

As I have posted before there are quite a few strongly correlated electron materials which exhibit a non-classical interlayer magnetoresistance. Specifically, it has dependence on the field direction which is the opposite to that expected from simple Lorentz force arguments.

This week I read a really nice paper Negative Interlayer Magnetoresistance and Zero-Mode Landau Level in Multilayer Dirac Electron Systems by Toshihito Osada.
The main result is the following expression for the interlayer conductivity in a tilted magnetic field.
A PRL makes an impressive comparison of the theory to experiments on an organic charge transfer salt.

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