345 citations · 3.3k across the 82 of their papers we have counts for
60 papers · 1 filter
Giant Conductance Enhancement in Graphene Nanoscrolls via Interlayer-Coupled States
Jia-Cheng Li, Ying-Je Lee, Yu An Cheng +6
Graphene nanoscrolls form a unique radial superlattice whose geometry enables transport behaviors distinct from their flat counterparts. We theoretically demonstrate that rolling a…
Genus-protected higher-order topological phases
Shahroze Shahab, Hui Liu, Daniel Varjas +1
Higher-order topological phases (HOTPs) feature protected gapless modes on boundaries of higher codimension, such as the corners or hinges of a crystal. They are understood as bein…
Non-Hermitian topology of quantum spin-Hall systems to detect edge-state polarization
Raghav Chaturvedi, Ion Cosma Fulga, Jeroen van den Brink +1
We study the non-Hermitian topology of multi-terminal transport in a quantum spin-Hall device described by the Bernevig-Hughes-Zhang model. We show that breaking time-reversal symm…
Non-Hermitian topological devices with Chern insulators
Kyrylo Ochkan, Michael Wissmann, Louis Veyrat +9
Multi-terminal topological devices are a new generation of electronic devices with quantized properties robust against imperfections. In magnetic topological insulators, dissipatio…
Noise resilience of two-dimensional Floquet topological phases
Balaganchi A. Bhargava, Sanjib Kumar Das, Lukas M. Sieberer +1
We study the effect of noise on two-dimensional periodically driven topological phases, focusing on two examples: the anomalous Floquet-Anderson phase and the disordered Floquet-Ch…
Topological properties of domain walls in antiferromagnetic topological insulators
Gabriele Naselli, Ion Cosma Fulga
Motivated by the study of stacking faults in weak topological insulators and the observation of magnetic domain walls in MnBiTe, we explore the topological properti…
Non-Hermitian topology in the quantum Hall effect of graphene
Burak Özer, Kyrylo Ochkan, Raghav Chaturvedi +12
Quantum Hall phases have recently emerged as a platform to investigate non-Hermitian topology in condensed-matter systems. This platform is particularly interesting due to its tuna…
Majorana-metal transition in a disordered superconductor: percolation in a landscape of topological domain walls
V. A. Zakharov, I. C. Fulga, G. Lemut +2
Most superconductors are thermal insulators. A disordered chiral -wave superconductor, however, can make a transition to a thermal metal phase. Because heat is then tra…
Network model for magnetic higher-order topological phases
Hui Liu, Ali G. Moghaddam, Daniel Varjas +1
We propose a network-model realization of magnetic higher-order topological phases (HOTPs) in the presence of the combined space-time symmetry -- the product of a…
Non-Hermitian topology of transport in the quantum Hall phases in graphene
Raghav Chaturvedi, Viktor Könye, Ewelina M. Hankiewicz +2
It has recently been shown that signatures of non-Hermitian topology can be realized in a conventional quantum Hall device connected to multiple current sources. These signatures m…
Stability of Weyl node merging processes under symmetry constraints
Gabriele Naselli, György Frank, Dániel Varjas +4
Changes in the number of Weyl nodes in Weyl semimetals occur through merging processes, usually involving a pair of oppositely charged nodes. More complicated processes involving m…
Two-point spectroscopy of Fibonacci topoelectrical circuits
Selma Franca, Torsten Seidemann, Fabian Hassler +2
Topoelectrical circuits are meta-material realizations of topological features of condensed matter systems. In this work, we discuss experimental methods that allow a fast and stra…
Non-Hermitian topological ohmmeter
Viktor Könye, Kyrylo Ochkan, Anastasiia Chyzhykova +4
Measuring large electrical resistances forms an essential part of common applications such as insulation testing, but suffers from a fundamental problem: the larger the resistance,…
Lack of near-sightedness principle in non-Hermitian systems
Helene Spring, Viktor Könye, Anton R. Akhmerov +1
The non-Hermitian skin effect is a phenomenon in which an extensive number of states accumulates at the boundaries of a system. It has been associated to nontrivial topology, with…
Observation of non-Hermitian topology in a multi-terminal quantum Hall device
Kyrylo Ochkan, Raghav Chaturvedi, Viktor Könye +10
Quantum devices characterized by non-Hermitian topology are predicted to show highly robust and potentially useful properties, but realizing them has remained a daunting experiment…
Geometry-independent tight-binding method for massless Dirac fermions in two dimensions
Alexander Ziesen, Ion Cosma Fulga, Fabian Hassler
The Nielsen-Ninomiya theorem, dubbed `fermion-doubling', poses a problem for the naive discretization of a single (massless) Dirac cone on a two-dimensional surface. The inevitable…
Phase transitions of wave packet dynamics in disordered non-Hermitian systems
Helene Spring, Viktor Könye, Fabian A. Gerritsma +2
Disorder can localize the eigenstates of one-dimensional non-Hermitian systems, leading to an Anderson transition with a critical exponent of 1. We show that, due to the lack of en…
Mixed higher-order topology: boundary non-Hermitian skin effect induced by a Floquet bulk
Hui Liu, Ion Cosma Fulga
We show that anomalous Floquet topological insulators generate intrinsic, non-Hermitian topology on their boundary. As a consequence, removing a boundary hopping from the time-evol…
Disorder effects on triple-point fermions
Hsiu-Chuan Hsu, Ion Cosma Fulga, Jhih-Shih You
The stability of three-dimensional relativistic semimetals to disorder has recently attracted great attention, but the effect of disorder remains elusive for multifold fermions, th…
Magnetic warping in topological insulators
Gabriele Naselli, Ali G. Moghaddam, Solange Di Napoli +4
We analyze the electronic structure of topological surface states in the family of magnetic topological insulators MnBiTe. We show that, at natural-cleavage surface…
Quantum phase transitions and a disorder-based filter in a Floquet system
Balaganchi A. Bhargava, Sanjib Kumar Das, Ion Cosma Fulga
Two-dimensional periodically-driven topological insulators have been shown to exhibit numerous topological phases, including ones which have no static analog, such as anomalous Flo…
Topological reflection matrix
Selma Franca, Fabian Hassler, Ion Cosma Fulga
While periodically-driven phases offer a unique insight into non-equilibrium topology that is richer than its static counterpart, their experimental realization is often hindered b…
Chirality flip of Weyl nodes and its manifestation in strained MoTe
Viktor Könye, Adrien Bouhon, Ion Cosma Fulga +3
Due to their topological charge, or chirality, the Weyl cones present in topological semimetals are considered robust against arbitrary perturbations. One well-understood exception…
Non-Hermitian skin effect of dislocations and its topological origin
Balaganchi A. Bhargava, Ion Cosma Fulga, Jeroen van den Brink +1
We demonstrate that dislocations in two-dimensional non-Hermitian systems can give rise to density accumulation or depletion through the localization of an extensive number of stat…