Suppose the semimetal - the solid material, in which the conducting and valence zones are intersected at isolated points - the so-called Weyl nodes. Near this points, the Hamiltonian of electrons is effectively reduced to the Weyl-like Hamiltonian, HW=±vFσ⋅(p−p±) where "±" is what we called the chirality in solid bodies, and vF<1 is the velocity of their propagation.
Suppose p±=±b, so that there is non-zero distance 2b between the Weyl nodes for left and right fermions in momentum space. Such semimetal is the particular case of so-called Weyl semimetal.
How to explain qualitatively that non-zero b implies the existence of anomalous Hall effect (AHE), namely, the current JAHE≃e22π[b×E], in presence of electric field?
No comments:
Post a Comment