中文
相关论文

相关论文: Supercritical Coulomb center and excitonic instabi…

200 篇论文

The supercritical instability in a system of two identical charged impurities in gapped graphene described in the continuous limit by the two-dimensional Dirac equation has been studied. The case where the charge of each impurity is…

强关联电子 · 物理学 2017-07-27 Oleksandr Sobol

We calculate exactly the vacuum polarization charge density in the field of a subcritical Coulomb impurity, $Z|e|/r$, in graphene. Our analysis is based on the exact electron Green's function, obtained by using the operator method, and…

介观与纳米尺度物理 · 物理学 2008-02-25 Ivan S. Terekhov , Alexander I. Milstein , Valeri N. Kotov , Oleg P. Sushkov

We propose that an excitonic gap can be generated along nodal directions by Coulomb interaction in the mixed state of d-wave cuprate superconductors. In a superconductor, the Coulomb interaction usually can not generate any fermion gap…

超导电性 · 物理学 2015-05-13 Hua Jiang , Guo-Zhu Liu , Geng Cheng

We obtain a novel bound state spectrum of the low energy excitations near the Fermi points of graphene in the presence of a charge impurity. The effects of possible short range interactions induced by the impurity are modelled by suitable…

高能物理 - 理论 · 物理学 2009-11-13 Kumar S. Gupta , Siddhartha Sen

In this paper, we numerically study a Coulomb impurity problem for interacting Dirac fermions restricted in disordered graphene quantum dots. In the presence of randomly distributed lattice defects and spatial potential fluctuations, the…

介观与纳米尺度物理 · 物理学 2020-11-25 Mustafa Polat , A. D. Güçlü

The question of whether the Coulomb interaction is strong enough to break the sublattice symmetry of un-doped graphene is discussed. We formulate a strong coupling expansion where the ground state of the Coulomb Hamiltonian is found exactly…

高能物理 - 理论 · 物理学 2015-05-30 Gordon W. Semenoff

We show that the emergent relativistic symmetry of electrons in graphene near its quantum critical point (QCP) implies a crucial importance of the Coulomb interaction. We derive scaling laws, valid near the QCP, that dictate the nontrivial…

介观与纳米尺度物理 · 物理学 2015-05-13 Daniel E. Sheehy , Joerg Schmalian

We give a brief summary of the current status of the electron many-body problem in graphene. We claim that graphene has intrinsic dielectric properties which should dress the interactions among the quasiparticles, and may explain why the…

强关联电子 · 物理学 2012-06-07 Bruno Uchoa , James P. Reed , Yu Gan , Young Il Joe , Diego Casa , Eduardo Fradkin , Peter Abbamonte

We investigate the quasi-bound states of a Coulomb impurity in graphene in the presence of a magnetic field. \ These states exhibit the dramatic and rather rare property of discrete scale invariance when the Coulomb potential is…

介观与纳米尺度物理 · 物理学 2021-09-14 Hailong Li , Haiwen Liu , Robert Joynt , X. C. Xie

We investigate the excitonic instability in the theory of Dirac fermions in graphene with long-range Coulomb interaction. We analyze the electron-hole vertex relevant for exciton condensation in the ladder approximation, showing that it…

介观与纳米尺度物理 · 物理学 2013-05-30 J. Gonzalez

We investigate the problem of dynamical gap generation in suspended graphene by long-range Coulomb interactions at strong coupling with Dyson-Schwinger equations. Including renormalization effects on the Fermi velocity we obtain a critical…

强关联电子 · 物理学 2013-02-12 C. Popovici , C. S. Fischer , L. von Smekal

I will discuss the gap and Bethe-Salpeter equations for quantum chromodynamics in Coulomb gauge under a leading order truncation scheme. Within this scheme, the role of charge conservation and the cancellation of infrared divergences…

高能物理 - 唯象学 · 物理学 2012-12-20 Peter Watson , Hugo Reinhardt

We study the problem of the electron excitation spectrum in the presence of point-like and regularized Coulomb impurities in gapped graphene. To this end, we use the Dirac model and in the point-like case theory of self-adjoint extensions…

介观与纳米尺度物理 · 物理学 2020-08-26 A. I. Breev , R. Ferreira , D. M. Gitman , B. L. Voronov

The effect of Coulomb interaction in an ensemble of Dirac fermions on the formation of superconducting pairing in monolayer and bilayer doped graphene is studied using the Kohn-Luttinger mechanism disregarding the Van der Waals potential of…

超导电性 · 物理学 2015-01-19 M. Yu. Kagan , V. A. Mitskan , M. M. Korovushkin

We discuss the conditions under which the predicted (but not yet observed) zero-field interlayer excitonic condensation in double layer graphene has a critical temperature high enough to allow detection. Crucially, disorder arising from…

介观与纳米尺度物理 · 物理学 2013-12-16 D. S. L. Abergel , M. Rodriguez-Vega , Enrico Rossi , S. Das Sarma

Coulomb interaction is of central importance in localized energy levels (bound states) or electronic flat bands and could result in many exotic quantum phases, such as magnetic, superconducting, and topological phases in graphene…

介观与纳米尺度物理 · 物理学 2020-08-25 Zhong-Qiu Fu , Ke-Ke Bai , Ya-Ning Ren , Jiao-Jiao Zhou , Lin He

In this paper, we consider the spectral properties of the bilayer graphene with the local excitonic pairing interaction between the electrons and holes. We consider the generalized Hubbard model, which includes both intralayer and…

介观与纳米尺度物理 · 物理学 2017-12-22 V. Apinyan , T. K. Kopeć

We present ab initio many-body calculations of the optical absorption in bulk graphite, graphene and bilayer of graphene. Electron-hole interaction is included solving the Bethe-Salpeter equation on top of a GW quasiparticle electronic…

材料科学 · 物理学 2015-05-14 Paolo E. Trevisanutto , Markus Holzmann , Michel Cote , Valerio Olevano

We address the problem of a Coulomb impurity in graphene in the presence of a perpendicular uniform magnetic field. We show that the problem can be solved below the supercritical impurity magnitude within the WKB approximation. Without…

强关联电子 · 物理学 2012-04-24 Yuhui Zhang , Yafis Barlas , Kun Yang

We reveal a new type of supercritical behavior in gapped graphene with two oppositely charged impurities by studying the two-dimensional Dirac equation for quasiparticles with the Coulomb potential regularized at small distances accounting…

强关联电子 · 物理学 2015-12-14 E. V. Gorbar , V. P. Gusynin , O. O. Sobol