Transmission Spectrum vs bandstructure

[Nayab Shiraz]

Is is true that the number of bands crossing the fermi energy level should be equal to the transmission coefficient at fermi level?

[Petr Khomyakov]

I would say vice versa. The transmission coefficient of a perfect bulk system for a given energy (e.g., the Fermi energy), spin, and (k_A, k_B)-point (A and B are directions perpendicular to the transport direction) is given by the number of band crossings given by solution of the following equation E(k_A, k_B, k_C) = E_Fermi with respect to k_C.

If one wants to account for spin degeneracy, one should multiply the transmission coefficient by a factor of 2. To get the total transmission for a given energy, one has to integrate it over the 2D Brillouin zone, i.e., over k_A and k_B.

[Nayab Shiraz]

Thank you so much for clarification