148 citations · 581 across the 21 of their papers we have counts for
21 papers
Imaging orbital Rashba induced charge transport anisotropy
Eylon Persky, Xi Wang, Giacomo Sala +8
Identifying orbital textures and their effects on the electronic properties of quantum materials is a critical element in developing orbitronic devices. However, orbital effects ar…
Transport effects of twist-angle disorder in mesoscopic twisted bilayer graphene
Aleksander Sanjuan Ciepielewski, Jakub Tworzydło, Timo Hyart +1
Magic-angle twisted bilayer graphene is a tunable material with remarkably flat energy bands near the Fermi level, leading to fascinating transport properties and correlated states…
Pentagonal nanowires from topological crystalline insulators: a platform for intrinsic core-shell nanowires and higher-order topology
Ghulam Hussain, Giuseppe Cuono, Piotr Dziawa +12
We report on the experimental realization of Pb1-xSnxTe pentagonal nanowires (NWs) with [110] orientation using molecular beam epitaxy techniques. Using first-principles calculatio…
Topology of chalcogen chains
Adam Kłosiński, Wojciech Brzezicki, Alexander Lau +4
We investigate the topological properties of the helical atomic chains occurring in elemental selenium and tellurium. We postulate a realistic model that includes spin-orbit intera…
Engineering axion insulator phase in superlattices with inversion symmetry breaking
Rajibul Islam, Sougata Mardanya, Alexander Lau +6
We study theoretically the interplay between magnetism and topology in three-dimensional HgTe/MnTe superlattices stacked along the (001) axis. Our results show the evolution of the…
Transport signatures of Van Hove singularities in mesoscopic twisted bilayer graphene
Aleksander Sanjuan Ciepielewski, Jakub Tworzydło, Timo Hyart +1
Magic-angle twisted bilayer graphene exhibits quasi-flat low-energy bands with Van Hove singularities close to the Fermi level. These singularities play an important role in the ex…
Universal suppression of superfluid weight by disorder independent of quantum geometry and band dispersion
Alexander Lau, Sebastiano Peotta, Dmitry I. Pikulin +2
Motivated by the experimental progress in controlling the properties of the energy bands in superconductors, significant theoretical efforts have been devoted to study the effect o…
Topological states in superlattices of HgTe-class materials for engineering three-dimensional flat bands
Rajibul Islam, Barun Ghosh, Giuseppe Cuono +7
In search of materials with three-dimensional flat band dispersions, using {\em ab-initio} computations, we investigate how topological phases evolve as a function of hydrostatic p…
Designing three-dimensional flat bands in nodal-line semimetals
Alexander Lau, Timo Hyart, Carmine Autieri +2
Electrons with large kinetic energy have a superconducting instability for infinitesimal attractive interactions. Quenching the kinetic energy and creating a flat band renders an i…
Bulk-boundary-defect correspondence at disclinations in rotation-symmetric topological insulators and superconductors
Max Geier, Ion Cosma Fulga, Alexander Lau
We study a link between the ground-state topology and the topology of the lattice via the presence of anomalous states at disclinations -- topological lattice defects that violate…
Topological phases without crystalline counterparts
Daniel Varjas, Alexander Lau, Kim Pöyhönen +3
Recent years saw the complete classification of topological band structures, revealing an abundance of topological crystalline insulators. Here we theoretically demonstrate the exi…
The influence of lattice termination on the edge states of the quantum spin Hall insulator monolayer -WTe
Alexander Lau, Rajyavardhan Ray, Daniel Varjas +1
We study the influence of sample termination on the electronic properties of the novel quantum spin Hall insulator monolayer -WTe. For this purpose, we construct an accura…
Novel topological insulators from crystalline symmetries
Alexander Lau, Carmine Ortix
We discuss recent advances in the study of topological insulators protected by spatial symmetries by reviewing three representative, theoretical examples. In three dimensions, thes…
Topological semimetals in the SnTe material class: Nodal lines and Weyl points
Alexander Lau, Carmine Ortix
We theoretically show that IV-VI semiconducting compounds with low-temperature rhombohedral crystal structure represent a new potential platform for topological semimetals. By mean…
Synthesizing Weyl semimetals in weak topological insulator and topological crystalline insulator multilayers
Alexander Lau, Carmine Ortix
We propose a different route to time-reversal invariant Weyl semimetals employing multilayer heterostructures comprising ordinary "trivial" insulators and nontrivial insulators wit…
Generic coexistence of Fermi arcs and Dirac cones on the surface of time-reversal invariant Weyl semimetals
Alexander Lau, Klaus Koepernik, Jeroen van den Brink +1
The hallmark of Weyl semimetals is the existence of open constant-energy contours on their surface -- the so-called Fermi arcs -- connecting Weyl points. Here, we show that for tim…
Topological Mirror Insulators in One Dimension
Alexander Lau, Jeroen van den Brink, Carmine Ortix
We demonstrate the existence of topological insulators in one dimension protected by mirror and time-reversal symmetries. They are characterized by a nontrivial topo…
Topological Edge States with Zero Hall Conductivity in a Dimerized Hofstadter Model
Alexander Lau, Carmine Ortix, Jeroen van den Brink
The Hofstadter model is a simple yet powerful Hamiltonian to study quantum Hall physics in a lattice system, manifesting its essential topological states. Lattice dimerization in t…
One-dimensional Dirac electrons on the surface of weak topological insulators
Alexander Lau, Carmine Ortix, Jeroen van den Brink
We show that a class of weak three-dimensional topological insulators feature one-dimensional Dirac electrons on their surfaces. Their hallmark is a line-like energy dispersion alo…
Topological surface states and Andreev bound states in superconducting iron pnictides
Alexander Lau, Carsten Timm
The nontrivial topology of the electronic structure of iron pnictides can lead to the appearance of surface states. We study such states in various strip geometries with a focus on…
Topological Surface States in Paramagnetic and Antiferromagnetic Iron Pnictides
Alexander Lau, Carsten Timm
The electronic structure of iron pnictides is topologically nontrivial, leading to the appearance of Dirac cones in the band structure for the antiferromagnetic phase. Motivated by…