Subatomic, High Energy and Plasma Physics seminar: Eric Nilsson

Abstract: The anomalous transport properties of strange metals, such as those found in high-temperature superconductors, remain one of the central unsolved problems in condensed matter physics. These materials appear to defy conventional quasiparticle descriptions, suggesting that their behavior is governed by quantum critical dynamics. The applicability of standard many-body methods to such strongly correlated systems is therefore severely limited, but holographic duality (“AdS/CFT”) offers a controlled framework to study such systems through their correspondence with near-extremal AdS black holes.

In this talk, I will focus on two-dimensional quantum critical theories with strongly broken translational symmetry, introduced through a spatially varying chemical potential lattice of zero average. The combination of quantum criticality and the absence of an intrinsic scale leads to distinctive macroscopic behavior. Remarkably, we find that these systems exhibit transport properties analogous to those predicted by Effective Medium Theory: inhomogeneous media where the current preferentially flows through the path of least resistance, producing effective transport coefficients distinct from that of the constituent regions.

In particular, this framework naturally reproduces the experimentally observed B-linear magnetoresistance seen in strange metals, paving the way toward a unified holographic description of the strange metal phase.