Interaction effects in the conductivity of high-mobility Si MOSFETs
Seminar Room 1, Newton Institute
The beginning of the 80s witnessed a triumph of the scaling theory of localization and the theory of electron-electron interactions in disordered conductors: the low-temperature behavior of the conductivity of numerous low-dimensional systems has been successfully attributed to the quantum interference effects. Curiously, application of these ideas to the two-dimensional electron liquid in Si MOSFETs - one of the most ubiquitous 2D systems - remained a challenge for more than 25 years. Over the last decade, an increase of the conductivity with cooling was observed for many high-mobility and low-density systems (p- and n-type GaAs/AlGaAs, SiGe, etc.), and the terms "anomalous metal in 2D" and "apparent 2D metal-insulator transition" have been introduced. I will discuss recent progress in our understanding of these phenomena, in particular, the "metallicity" of high-mobility Si MOSFETs and the renormalization of Fermi-liquid parameters at low densities.