[Special seminar] Hyun-Jung Lee from POSTECH
Title : Multifractality at the Anderson-Mott transition
Speaker : Hyun-Jung Lee from POSTECH
In this talk, we discuss non-ergodic (glassy) features exhibited in the vicinity of the Anderson-Mott transition such as an increasing magnetic susceptibility and specific-heat coefficient attributed to the formation of local moments. An important unresolved question of the issue is how the local moments interact with the conduction electrons that becomes localized at the metal-insulator transition, whose answer is of vital importance for the interpretation of transport experiments in doped semiconductors such as Si:P, Si:P,B, and Si:B. In a theoretical point of view, it is a very difficult problem of constructing a self-consistent theory for the metal-insulator transition that takes into account the disordered conduction electrons, local moment formation and Kondo physics in disordered systems. As a first step, we studied the interaction-driven localization transition of the disordered, Coulombinteracting spinless fermions within the Hartree-Fock/Ewald method and performed a multifractal scaling analysis to elucidate the quantum criticality at the Anderson-Mott transition. The extension to the spinful case is also undertaken to look into the possibility for long-range spin order or spin-glass phase near the metal-insulator transition, of which we present preliminary results.