English
Related papers

Related papers: Z2 topological invariants in two dimensions from q…

200 papers

Using a combined perturbative and self-consistent mean-field approach that we directly compare with quantum Monte Carlo calculations, we study the effects of short-ranged interactions on the $Z_2$ topological insulator phase, also known as…

Strongly Correlated Electrons · Physics 2014-11-19 Hsin-Hua Lai , Hsiang-Hsuan Hung , Gregory A. Fiete

The fractional quantum Hall effect has recently been shown to exist in heterostructures of van der Waals materials without an externally applied magnetic field, e.g. in twisted bilayers of MoTe$_2$. These fractional Chern insulators break…

Strongly Correlated Electrons · Physics 2025-09-23 Sahana Das , Glenn Wagner , Titus Neupert

The Z2 topological invariant is defined in the chiral d-wave superconductor having a triangular lattice in the presence of the 120 degrees magnetic ordering. By analyzing the Z2 invariant, we determine the conditions of implementing…

Superconductivity · Physics 2018-05-23 Valery V. Val'kov , Anton O. Zlotnikov , Maxim S. Shustin

The effects of static disorder on the Z_2 quantum spin-Hall effect for non-interacting electrons propagating in two-dimensional space is studied numerically. A two-dimensional time-reversal symmetric network model is constructed to account…

Mesoscale and Nanoscale Physics · Physics 2007-08-02 Hideaki Obuse , Akira Furusaki , Shinsei Ryu , Christopher Mudry

We study a $U(1)\times U(1)$ system in (2+1)-dimensions with long-range interactions and mutual statistics. The model has the same form after the application of operations from the modular group, a property which we call modular invariance.…

Statistical Mechanics · Physics 2013-05-30 Scott D. Geraedts , Olexei I. Motrunich

Time-reversal symmetric topological insulator is a novel state of matter that a bulk-insulating state carries dissipationless spin transport along the surfaces, embedded by the $Z_2$ topological invariant. In the noninteracting limit, this…

Strongly Correlated Electrons · Physics 2015-03-12 Hsin-Hua Lai , Hsiang-Hsuan Hung

We present a general recipe to describe topological phase transitions in condensed matter systems with interactions. We show that topological invariants in the presence of interactions can be efficiently calculated by means of a…

Materials Science · Physics 2025-08-07 S. S. Krishtopenko , A. V. Ikonnikov , F. Hartmann , S. Höfling , B. Jouault , F. Teppe

We study the band structure of phases induced by depositing bilayer graphene on a transition metal dichalcogenide monolayer. Tight-binding and low-energy effective Hamiltonian calculations show that it is possible to induce topologically…

Mesoscale and Nanoscale Physics · Physics 2018-06-20 Abdulrhman M. Alsharari , Mahmoud M. Asmar , Sergio E. Ulloa

The topological invariants of gapped time reversal invariant lattice superconductors are studied by mapping the superconducting mean field Hamiltonian to a Bloch Hamiltonian. There is a single $Z_2 $ invariant in two dimensions and four…

Superconductivity · Physics 2007-05-23 Rahul Roy

We present an exact solution of a modifed Dirac equation for topological insulator in the presence of a hole or vacancy to demonstrate that vacancies may induce bound states in the band gap of topological insulators. They arise due to the…

Mesoscale and Nanoscale Physics · Physics 2011-07-22 Wen-Yu Shan , Jie Lu , Hai-Zhou Lu , Shun-Qing Shen

We investigate the role of quantum fluctuations in topological quantum phase transitions of quantum spin Hall insulators and quantum anomalous Hall insulators. Employing the variational cluster approximation to obtain the single-particle…

Strongly Correlated Electrons · Physics 2014-04-08 Jan Carl Budich , Ronny Thomale , Gang Li , Manuel Laubach , Shou-Cheng Zhang

We study interaction induced topological phase transition in Bernevig-Hughes-Zhang model. Topological nature of the phase transition is revealed by directly calculating the Z2 index of the interacting system from the single-particle Green's…

Strongly Correlated Electrons · Physics 2012-06-26 Lei Wang , Xi Dai , X. C. Xie

Topological phases with insulating bulk and gapless surface or edge modes have attracted much attention because of their fundamental physics implications and potential applications in dissipationless electronics and spintronics. In this…

Materials Science · Physics 2016-05-18 Yafei Ren , Zhenhua Qiao , Qian Niu

We proposed a formula for the $Z_2$ invariant for topological insulators, which remains valid without translational invariance. Our formula is a local expression, in the sense that the contributions mainly come from quantities near a point.…

Mesoscale and Nanoscale Physics · Physics 2019-11-07 Zhi Li , Roger S. K. Mong

Finding new physical responses that signal topological quantum phase transitions is of both theoretical and experimental importance. Here, we demonstrate that the piezoelectric response can change discontinuously across a topological…

Mesoscale and Nanoscale Physics · Physics 2020-05-12 Jiabin Yu , Chao-Xing Liu

We propose an interferometric method to measure Z2 topological invariants of time-reversal invariant topological insulators realized with optical lattices in two and three dimensions. We suggest two schemes which both rely on a combination…

Quantum Gases · Physics 2014-04-30 Fabian Grusdt , Dmitry Abanin , Eugene Demler

We consider a gapped periodic quantum system with time-reversal symmetry of fermionic (or odd) type, i.e. the time-reversal operator squares to -1. We investigate the existence of periodic and time-reversal invariant Bloch frames in…

Mathematical Physics · Physics 2016-06-21 Domenico Fiorenza , Domenico Monaco , Gianluca Panati

In the strictly periodic setting, the electric polarization of inversion-symmetric solids with and without time-reversal symmetry and the isotropic magneto-electric response function of time-reversal symmetric insulators are known to be…

Disordered Systems and Neural Networks · Physics 2015-11-11 Juntao Song , Emil Prodan

We introduce $\mathbb Z_2$-valued bulk invariants for symmetry-protected topological phases in $2+1$ dimensional driven quantum systems. These invariants adapt the $W_3$-invariant, expressed as a sum over degeneracy points of the…

Mesoscale and Nanoscale Physics · Physics 2018-01-24 Bastian Höckendorf , Andreas Alvermann , Holger Fehske

Topological quantum state described by the global invariant has been extensively studied in theory and experiment. In this letter, we investigate the relationship between \emph{Zitterbewegung} and the topology of systems that reflect the…

Quantum Physics · Physics 2022-11-23 Xin Shen , Yan-Qing Zhu , Zhi Li