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Van Hove singularities enhance many-body interactions and induce collective states of matter ranging from superconductivity to magnetism. In magic-angle twisted bilayer graphene, van Hove singularities appear at low energies and are…

Mesoscale and Nanoscale Physics · Physics 2024-08-19 Suvronil Datta , Saisab Bhowmik , Harsh Varshney , Kenji Watanabe , Takashi Taniguchi , Amit Agarwal , U. Chandni

Cosine-shaped bands that occur in DFT-based electronic band structures for MgB2 are further analyzed with calculations along reciprocal directions parallel to the high symmetry G-A direction at regular intervals along G-M. Band degeneracies…

Superconductivity · Physics 2026-03-24 Jose A. Alarco , Ian D. R. Mackinnon

We use the quasistatic approach to analyze the criterion of ferromagnetism for two-dimensional (2D) systems with the Fermi level near Van Hove singularities (VHS) of the electronic spectrum. It is shown that the spectrum of spin excitations…

Strongly Correlated Electrons · Physics 2012-09-20 P. A. Igoshev , A. A. Katanin , V. Yu. Irkhin

Due to the diverging density of states (DOS), Van Hove singularities (VHS) near the Fermi level are known to boost the susceptibility to a wide variety of electronic instabilities, including superconductivity. We theoretically show that the…

Superconductivity · Physics 2024-04-09 Hyeok-Jun Yang , Yi-Ting Hsu

We show that in three-dimensional (3D) topological metals, a subset of the van Hove singularities of the density of states sits exactly at the transitions between topological and trivial gapless phases. We may refer to these as topological…

Mesoscale and Nanoscale Physics · Physics 2021-11-30 Pierpaolo Fontana , Michele Burrello , Andrea Trombettoni

Materials hosting flat bands at the vicinity of the Fermi level promote exotic symmetry broken states. Common to many of these are van Hove singularities at saddle points of the dispersion or even higher-order van Hove singularities where…

Quantum materials with layered kagome structures have drawn considerable attention due to their unique lattice geometry, which gives rise to flat bands co-existing with Dirac-like dispersions. The interplay between strong Coulomb…

Hyperbolic metamaterials (HMM) are artificially engineered materials that are congenial for light-matter interaction studies and nanophotonic applications with the hyperbolic dispersion of light propagating through them, which offers a…

Optics · Physics 2025-05-13 Amitrajit Nag , Jaydeep K. Basu

Van Hove singularities (VHss) in the vicinity of the Fermi energy often play a dramatic role in the physics of strongly correlated electron materials. The divergence of the density of states generated by VHss can trigger the emergence of…

When a van-Hove singularity is located in the vicinity of the Fermi level, the electronic scattering rate acquires a non-analytic contribution. This invalidates basic assumptions of Fermi liquid theory and within perturbative treatments…

Strongly Correlated Electrons · Physics 2010-10-20 Sebastian Schmitt

Observation of robust superconductivity in some of the iron based superconductors in the vicinity of a Lifshitz point where a spin density wave instability is suppressed as the {hole} band drops below the Fermi energy raise questions for…

Superconductivity · Physics 2016-08-30 Vivek Mishra , Douglas J. Scalapino , Thomas A. Maier

The superconducting phase of hydrogen sulfide at Tc=200 K observed by Drozdov and collaborators at pressures around 200 GPa is simple bcc Im-3m H3S, predicted beforehand by Duan {\it et al.}, has experimental confirmation. The various…

Superconductivity · Physics 2016-03-30 Yundi Quan , Warren E. Pickett

By using a well established 'ab initio' theoretical approach developed in the past to quantitatively study the superconductivity of condensed matter systems, which is based on the Kohn-Sham Density Functional theory, I study the superfluid…

Quantum Gases · Physics 2016-06-01 Francesco Ancilotto

We extend a top-down holographic model of a Weyl semimetal to finite charge density and compute the fermionic spectral function by introducing two probe fermions of opposite chirality. The model is controlled by the boundary fermion mass M…

High Energy Physics - Theory · Physics 2025-10-01 Cheng-Yuan Lu , Xian-Hui Ge , Sang-Jin Sin

The layered perovskite Sr$_2$RuO$_4$ serves as a model material of the two-dimensional (2D) Fermi liquid but also exhibits various emergent phenomena including the non-Fermi-liquid (NFL) behavior under external perturbations such as…

Strongly Correlated Electrons · Physics 2024-06-04 Rei Nishinakayama , Yoshiki J. Sato , Takayoshi Yamanaka , Yoshiteru Maeno , Hiroshi Yaguchi , Naoki Kikugawa , Ryuji Okazaki

We study the superconducting properties of population-imbalanced ultracold Fermi mixtures in one-dimensional (1D) optical lattices that can be effectively described by the spin-imbalanced attractive Hubbard model (AHM) in the presence of a…

Quantum Gases · Physics 2017-03-16 Andrzej Ptok , Agnieszka Cichy , Karen Rodríguez , Konrad J. Kapcia

In this paper, we investigate a holographic model of superconductor with hidden Fermi surfaces, which was defined by the logarithmic violation of area law of entanglement entropy. We works in fully back-reacted background using standard…

High Energy Physics - Theory · Physics 2013-11-19 ZhongYing Fan

We investigate the electron properties of the monolayer and bilayer silicene which is the honeycomb lattice consist of silicon atoms, including the optical conductivity and charged impurity scattering, due to the quasipatricle Dirac-like…

Strongly Correlated Electrons · Physics 2018-05-02 Chen-Huan Wu

Experiments on twisted double bilayer tungsten diselenide have demonstrated that moir'e semiconductors can realize a relativistic Mott transition, i.e., a quantum phase transition from a Dirac semimetal to a correlated insulating state, by…

Mesoscale and Nanoscale Physics · Physics 2025-11-05 Bilal Hawashin , Julian Kleeschulte , David Kurz , Aiman Al-Eryani , Michael M. Scherer

We present theoretical and experimental results exploring a half-Heusler compound TmPdSb with unusual band order and metallic surface states. Typically, the half-Heusler systems exhibit topological features in a semimetallic state, and…

Materials Science · Physics 2025-04-29 Shovan Dan , Andrzej Ptok , Orest Pavlosiuk , Karan Singh , Piotr Wiśniewski , Dariusz Kaczorowski