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Related papers: Type-II Weyl semimetal vs gravastar

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In metallic condensed matter systems two different types of Weyl fermions can in principle emerge, with either a vanishing (type-I) or with a finite (type-II) density of states at the Weyl node energy. So far only WTe2 and MoTe2 were…

Strongly Correlated Electrons · Physics 2016-05-25 K. Koepernik , D. Kasinathan , D. V. Efremov , Seunghyun Khim , Sergey Borisenko , Bernd Büchner , Jeroen van den Brink

In this paper we present a non-singular black hole model as a possible end-product of gravitational collapse. The depicted spacetime which is type [II,(II)], by Petrov classification, is an exact solution of the Einstein equations and…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Manasse R. Mbonye , Demosthenes Kazanas

For first-order topological semimetals, non-Hermitian perturbations can drive the Weyl nodes into Weyl exceptional rings having multiple topological structures and no Hermitian counterparts. Recently, it was discovered that higher-order…

Mesoscale and Nanoscale Physics · Physics 2021-11-11 Tao Liu , James Jun He , Zhongmin Yang , Franco Nori

In the present paper we propose a stellar model under the $f(\mathbb{T})$ gravity following the conjecture of Mazur-Mottola~[Report number: LA-UR-01-5067 (2001); Proc. Natl. Acad. Sci. USA 101 (2004) 9545] known in literature as {\it…

General Relativity and Quantum Cosmology · Physics 2020-03-25 Amit Das , Shounak Ghosh , Debabrata Deb , Farook Rahaman , Saibal Ray

Weyl fermions play a major role in quantum field theory but have been quite elusive as fundamental particles. Materials based on quasi two-dimensional bismuth layers were recently designed and provide an arena for the study of the interplay…

Strongly Correlated Electrons · Physics 2016-12-07 M. Chinotti , A. Pal , W. J. Ren , C. Petrovic , L. Degiorgi

The leading order correction to the metric of a Schwarzschild black hole, due to the backreaction of infalling fermionic matter fields, is shown to produce a shift of the event horizon such that particles that would constitute Hawking…

High Energy Physics - Theory · Physics 2009-10-30 Arundhati Dasgupta , Parthasarathi Majumdar

We propose a new topological quantum state of matter---the two-dimensional (2D) Weyl half semimetal (WHS), which features 2D Weyl points at Fermi level belonging to a single spin channel, such that the low-energy electrons are described by…

Materials Science · Physics 2019-08-28 Jing-Yang You , Cong Chen , Zhen Zhang , Xian-Lei Sheng , Shengyuan A. Yang , Gang Su

This paper investigates the gravastar model as a potential alternative to black holes, utilizing the Kuchowicz metric in the context of Rastall gravity. The model comprises three distinct regions: an interior with positive energy density…

General Relativity and Quantum Cosmology · Physics 2025-09-25 Tayyab Naseer , M. Sharif , Areej Tabassum

Weyl semimetals are gapless three-dimensional topological materials where two bands touch at even number of points in the Brillouin zone. In this work we study a zincblende lattice model realizing a time-reversal invariant Weyl semimetal.…

Mesoscale and Nanoscale Physics · Physics 2013-07-10 Teemu Ojanen

Topological Weyl semimetals (TWS) can be classified as type-I TWS, in which the density of states vanishes at the Weyl nodes, and type-II TWS where an electron and a hole pocket meet with finite density of states at the nodal energy. The…

Mesoscale and Nanoscale Physics · Physics 2017-03-01 Timothy M. McCormick , Itamar Kimchi , Nandini Trivedi

We present a parametric study of the spacetime structures obtainable in Weyl conformal gravity's dyonic Reissner-Nordstr\"{o}m solution. We derive expressions for photon sphere radii and horizons for this metric in terms of the conformal…

General Relativity and Quantum Cosmology · Physics 2026-02-05 Reinosuke Kusano , Miguel Yulo Asuncion , Keith Horne

Magnetic topological materials have recently drawn significant importance and interest, due to their topologically nontrivial electronic structure within spontaneous magnetic moments and band inversion. Based on first-principles…

Strongly Correlated Electrons · Physics 2018-07-20 R. Wang , Y. J. Jin , J. Z. Zhao , Z. J. Chen , Y. J. Zhao , H. Xu

Using the complete classification of the bases in the rotating black hole background we separate superradiance from the Hawking effect. We first find that there is spontaneous particle creation for fermions by the potential outside the…

General Relativity and Quantum Cosmology · Physics 2023-10-17 De-Chang Dai , Dejan Stojkovic

The band structure of a type-II Weyl semimetal has pairs of electron and hole pockets that coexist over a range of energies and touch at a topologically protected conical point. We identify signatures of this Weyl point in the magnetic…

Mesoscale and Nanoscale Physics · Physics 2016-06-16 T. E. O'Brien , M. Diez , C. W. J. Beenakker

We discuss a solution of the Einstein equations, obtained by gluing the external Kerr metric and the internal Weyl metric, describing an axisymmetric static vacuum distorted black hole. These metrics are glued at the null surfaces…

General Relativity and Quantum Cosmology · Physics 2015-06-23 Valeri P. Frolov , Andrei V. Frolov

Three-dimensional Weyl fermions are found to emerge from simple cubic lattices with staggered fluxes. The mechanism is to gap the quadratic band touching by time-reversal-symmetry-breaking hoppings. The system exhibits rich phase diagrams…

Quantum Gases · Physics 2012-04-03 Jian-Hua Jiang

Topological materials have been a main focus of studies in the past decade due to their protected properties that can be exploited for the fabrication of new devices. Among them, Weyl semimetals are a class of topological semimetals with…

Materials Science · Physics 2024-02-05 Davide Grassano , Luca Binci , Nicola Marzari

A gravastar comprises three distinct sections: the interior zone, the middle shell, and its outer region. By considering a specific extended teleparallel gravity model that incorporates conformal Killing vectors and provides the field…

General Relativity and Quantum Cosmology · Physics 2024-04-30 G. Mustafa , Faisal Javed , Arfa Waseem , S. K. Maurya , Ghulam Fatima

We have investigated the emerging conformal field theory behavior on the interior interface of the region near the cosmological event horizon on an example of massless Dirac fermions. Indeed, we have constructed and verified the emerging de…

General Relativity and Quantum Cosmology · Physics 2011-03-04 Pawel O. Mazur , Pawel J. Morawiec

We propose an analytical model describing Fermi arc surface states observed in the recent investigations of Weyl semimetals. The effective two-valley Hamiltonian is supplemented by the boundary conditions taking into account both the…

Mesoscale and Nanoscale Physics · Physics 2017-03-01 Zh. A. Devizorova , V. A. Volkov