We demonstrate that a disordered magnetic Weyl semimetal may be mapped onto a two-dimensional array of coupled replicated Hubbard chains, where the Hubbard U is directly related to the variance of the disorder potential. This is a three-dimensional generalization of a similar mapping of the two-dimensional quantum Hall plateau transition to a one-dimensional Hubbard chain. We demonstrate that...
Anomalous symmetries play a central role in modern physics, from quantum field theories (QFTs) in the infrared to lattice models in the ultraviolet. Typically, anomalous symmetries are characterized by their appearance on the boundary of symmetry-protected topological (SPT) phases. However, folklore has also treated several other phenomena—such as the obstruction to a single symmetric, gapped,...
We identify a new contribution to the conventional Hall effect that emerges in materials with $C_4K$ symmetry. This contribution originates from the effect of Berry curvature on phase space density. We demonstrate this using semiclassical equations of motion and identify corrections to Hall conductivity from Berry curvature and orbital magnetic moment effects. As an illustration, we build a...
Nanoscale defects such as Nitrogen Vacancy (NV) centers can serve as sensitive and non-invasive probes of electromagnetic fields and fluctuations from materials, which in turn can be used to characterize these systems. In this talk, which is based on our recent work[1], we will specifically discuss how NV centers can directly probe time-reversal symmetry breaking (TRSB) phenomena in...
Nd$_{0.4}$La$_{1.6-x}$Sr$_x$CuO$_4$ (Nd-LSCO) is a prototypical high T$_C$ cuprate superconductor. At a hole-doping of x = 0.125 = 1/8, this compound is notable for displaying both static spin stripe order and charge stripe order, as well as a heavily suppressed superconducting T$_C$ ~ 3 K. Previous high-field transport [1] and thermopower measurements [2] have shown that the electronic...
