Edge-Selective Extremal Damping from Topological Heritage of Dissipative Chern Insulators.

One of the most important practical hallmarks of topological matter is the presence of topologically protected, exponentially localized edge states at interfaces of regions characterized by unequal topological invariants. Here, we show that, even when driven far from their equilibrium ground state, Chern insulators can inherit topological edge features from their parent Hamiltonian. In particular, we show that the asymptotic long-time approach of the nonequilibrium steady state, governed by a Lindblad master equation, can exhibit edge-selective extremal damping.

Origin of the quasi-quantized Hall effect in ZrTe.

The quantum Hall effect (QHE) is traditionally considered to be a purely two-dimensional (2D) phenomenon. Recently, however, a three-dimensional (3D) version of the QHE was reported in the Dirac semimetal ZrTe. It was proposed to arise from a magnetic-field-driven Fermi surface instability, transforming the original 3D electron system into a stack of 2D sheets.

Unconventional Hall response in the quantum limit of HfTe.

Interacting electrons confined to their lowest Landau level in a high magnetic field can form a variety of correlated states, some of which manifest themselves in a Hall effect. Although such states have been predicted to occur in three-dimensional semimetals, a corresponding Hall response has not yet been experimentally observed. Here, we report the observation of an unconventional Hall response in the quantum limit of the bulk semimetal HfTe, adjacent to the three-dimensional quantum Hall effect of a single electron band at low magnetic fields.