Dirty higher-order Dirac semimetal: Quantum criticality and bulk-boundary correspondence

Dirty higher-order Dirac semimetal: Quantum criticality and bulk-boundary correspondence

Blog Article

We analyze the stability of time-reversal (T) and lattice fourfold (C_{4}) symmetry breaking three-dimensional higher-order topological (HOT) Dirac semimetals (DSMs) and the associated one-dimensional hinge modes in the presence of random pointlike charge impurities.Complementary real space numerical and momentum space renormalization group (RG) analyses suggest that a HOTDSM, while being a stable phase of matter for sufficiently weak disorder, undergoes a continuous quantum phase transition into a Adjustment pull Pin trivial metal at finite disorder.However, the corresponding critical exponents (numerically obtained from the scaling of the density of states) are extremely close to the ones found in a dirty, but first-order DSM that on the other hand preserves T and C_{4} symmetries, and Universal Griller Knob support two Fermi arc surface states.This observation suggests an emergent superuniversality (insensitive to symmetries) in the entire family of dirty DSMs, as also predicted by a leading-order RG analysis.

As a direct consequence of the bulk-boundary correspondence, the hinge modes in a system with open boundaries gradually fade away with increasing randomness, and completely dissolve in the trivial metallic phase at strong disorder.