Amorphous topological phases protected by continuous rotation symmetry

Spring, Helene; Akhmerov, A. R.; Varjas, Dániel

doi:10.21468/scipostphys.11.2.022

Cited by 24 publications

(12 citation statements)

References 47 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Prior work on topology in non-crystalline materials used convenient amorphous tight-binding models with average and local symmetries [11,[14][15][16]39], however these do not include the full chemical and structural specificity found in real matter. Similarly, real-space invariants [40][41][42][43], including Wannierbased tight-binding formalism, require the system be treated on a case-by-case basis and can be computationally costly.…”

mentioning

confidence: 99%

Structural spillage: an efficient method to identify non-crystalline topological materials

Muñoz-Segovia¹,

Corbae²,

Varjas³

et al. 2023

Preprint

View full text Add to dashboard Cite

While topological materials are not restricted to crystals, there is no efficient method to diagnose topology in non-crystalline solids such as amorphous materials. Here we introduce the structural spillage, a new indicator that predicts the unknown topological phase of a non-crystalline solid, which is compatible with first-principles calculations. We illustrate its potential with tight-binding and first-principles calculations of amorphous bismuth, predicting a bilayer to be a new topologically nontrivial material. Our work opens up the efficient prediction of non-crystalline solids via first-principles and high-throughput searches.

show abstract

mentioning

confidence: 99%

Structural spillage: an efficient method to identify non-crystalline topological materials

Muñoz-Segovia¹,

Corbae²,

Varjas³

et al. 2023

Preprint

View full text Add to dashboard Cite

show abstract

“…Currently, the research of topological states of matter has moved beyond crystalline solids to amorphous and quasicrystalline systems [36][37][38][39][40][41][42] . While it is not yet clear whether these states of matter exist in nature, they can be realized in artificial designer systems [43][44][45][46][46][47][48][49] .…”

mentioning

confidence: 99%

Topological random fractals

et al. 2022

View full text Add to dashboard Cite

The search for novel topological quantum states has recently moved beyond naturally occurring crystalline materials to complex and engineered systems. In this work we generalize the notion of topological electronic states to random lattices in non-integer dimensions. By considering a class D tight-binding model on critical clusters resulting from a two-dimensional site percolation process, we demonstrate that these topological random fractals exhibit the hallmarks of topological insulators. Specifically, our large-scale numerical studies reveal that topological random fractals display a robust mobility gap, support quantized conductance and represent a well-defined thermodynamic phase of matter. The finite-size scaling analysis further suggests that the critical properties are not consistent with the expectations of class D systems in two dimensions, hinting to the nontrivial relationship between fractal and integer-dimensional topological states. Our results establish topological random fractals as the most complex systems known to support nontrivial band topology with their distinct unique properties.

show abstract

“…A useful starting point in this endeavor is to consider crystals with perfect translational symmetry, and to include perturbative corrections due to the effects of weak disorder [5][6][7][8][9][10][11]. However, translational symmetry is not a prerequisite for realizing noninteracting topological phases, even in the absence of a well-defined momentum, an associated electronic "bandstructure" and the very notion of a Brillouin zone [12][13][14][15][16][17][18]. Interestingly, experiments on a candidate topological material [19] and a photonic system [20] provide promising evidence for the existence of topological phases in amorphous settings.…”

mentioning

confidence: 99%

Fractionalization and topology in amorphous electronic solids

Kim¹,

Agarwala²,

Chowdhury³

2022

Preprint

View full text Add to dashboard Cite

Band-topology is traditionally analyzed in terms of gauge-invariant observables associated with crystalline Bloch wavefunctions. Recent work has demonstrated that many of the free fermion topological characteristics survive even in an amorphous setting. In this work, we extend these studies to incorporate the effect of strong repulsive interactions on the fate of topology and other correlation induced phenomena. Using a parton-based approach, we obtain the interacting phase diagram for an electronic two-orbital model with tunable topology in a two dimensional amorphous network. In addition to the (non-)topological phases that are adiabatically connected to the free fermion limit, we find a number of strongly interacting amorphous analogs of crystalline Mott insulating phases with non-trivial chiral neutral edge modes, and a fractionalized Anderson insulating phase. The amorphous networks thus provide a new playground for studying a plethora of exotic states of matter, and their glassy dynamics, due to the combined effects of non-trivial topology, disorder, and strong interactions.

show abstract

Amorphous topological phases protected by continuous rotation symmetry

Cited by 24 publications

References 47 publications

Structural spillage: an efficient method to identify non-crystalline topological materials

Structural spillage: an efficient method to identify non-crystalline topological materials

Topological random fractals

Fractionalization and topology in amorphous electronic solids

Contact Info

Product

Resources

About