Kinetic magnetoelectric effect in topological insulators

This paper theoretically proposes a gigantic kinetic magnetoelectric effect (KME) in topological insulators, interpreting the results using topological surface currents. A theory of KME for a topological insulator's surface Hamiltonian is constructed, accurately describing results from direct numerical calculations. The KME's dependence on surface details highlights its non-bulk nature. Chern insulators and Z₂ topological insulators are proposed as platforms exhibiting a significantly larger KME (5–8 orders of magnitude) than metals due to surface current confinement. Cu₂ZnSnSe₄ is identified as a potential candidate material.

Ken Osumi, Tiantian Zhang, Shuichi Murakami