English
Related papers

Related papers: Undamped inter-valley paramagnons in doped graphen…

200 papers

Observations of electron-hole asymmetry in transport through graphene devices at high magnetic field challenge prevalent models of the graphene quantum Hall effect. Here, we study this asymmetry both in conventional magnetotransport and in…

Mesoscale and Nanoscale Physics · Physics 2021-11-23 Nicolas Moreau , Boris Brun , Sowmya Somanchi , Kenji Watanabe , Takashi Taniguchi , Christoph Stampfer , Benoît Hackens

We study the ground state properties of an ABA-stacked trilayer graphene. The low energy band structure can be described by a combination of both a linear and a quadratic particle-hole symmetric dispersions, reminiscent of monolayer- and…

Mesoscale and Nanoscale Physics · Physics 2012-03-08 Ralph van Gelderen , Lih-King Lim , C. Morais Smith

We theoretically study a doped graphene ribbon suspended over a trench and subject to an ac-electrical field polarized perpendicularly to the graphene plane. In such a system, the external ac-field is coupled to the relatively slow…

Mesoscale and Nanoscale Physics · Physics 2015-06-12 Axel M. Eriksson , Leonid Y. Gorelik

Raman spectroscopy is a fast, non-destructive means to characterize graphene samples. In particular, the Raman spectra show a significant dependence on doping. While the change in position and width of the G peak can be explained by the…

Materials Science · Physics 2015-05-13 D. M. Basko , S. Piscanec , A. C. Ferrari

We have formulated a theory for investigating the conditions which are required to achieve entangled states of electrons on graphene and three-dimensional (3D) topological insulators (TIs). We consider the quantum entanglement of spins by…

Mesoscale and Nanoscale Physics · Physics 2015-06-16 Andrii Iurov , Godfrey Gumbs

We theoretically argue that, in doped AB bilayer graphene, the electron-electron coupling can give rise to the spontaneous formation of fractional metal phases. These states, being generalizations of a more common half-metal, have a Fermi…

Mesoscale and Nanoscale Physics · Physics 2023-04-19 A. L. Rakhmanov , A. V. Rozhkov , A. O. Sboychakov , Franco Nori

We present a theory of collective spin excitations in diluted-magnetic-semiconductor quantum wells in which local magnetic moments are coupled via a quasi-two-dimensional gas of electrons or holes. In the case of a ferromagnetic state with…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 Diego Frustaglia , Jürgen König , Allan H. MacDonald

Although plasmon modes exist in doped graphene, the limited range of doping achieved by gating restricts the plasmon frequencies to a range that does not include visible and infrared. Here we show, through the use of first-principles…

Mesoscale and Nanoscale Physics · Physics 2018-05-30 Sharmila N. Shirodkar , Marios Mattheakis , Paul Cazeaux , Prineha Narang , Marin Soljačić , Efthimios Kaxiras

In this article we investigate the excitations in a single graphene layer and in a single-walled carbon nanotube, i.e. the spectrum of magnetic excitations is calculated. In the absence of interactions in these systems there is a unique gap…

Strongly Correlated Electrons · Physics 2015-06-19 Vladimir Posvyanskiy , Logi Arnarson , Per Hedegård

The electronic properties of twisted bilayer graphene (TBG) can be dramatically different from those of a single graphene layer, in particular when the two layers are rotated relative to each other by a small angle. TBG has recently…

We consider magic-angle graphene in the doping regime around charge neutrality and study the connection between a recently proposed inter-valley coherent insulator at zero doping and the neighboring superconducting domes. The magic-angle…

Strongly Correlated Electrons · Physics 2023-01-12 Vladyslav Kozii , Michael P. Zaletel , Nick Bultinck

We study RKKY interactions between local magnetic moments for both doped and undoped graphene. We find in both cases that the interactions are primarily ferromagnetic for moments on the same sublattice, and antiferromagnetic for moments on…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 L. Brey , H. A. Fertig , S. Das Sarma

In spin-polarized itinerant electron systems, collective spin-wave modes arise from dynamical exchange and correlation (xc) effects. We here consider spin waves in doped paramagnetic graphene with adjustable Zeeman-type band splitting. The…

Mesoscale and Nanoscale Physics · Physics 2022-01-05 Matthew J. Anderson , Florent Perez , Carsten A. Ullrich

Employing the recently developed momentum-space quantum Monte Carlo scheme, we study the dynamic response of single-particle and collective excitations in realistic continuum models of twisted bilayer graphene. At charge neutrality, this…

Strongly Correlated Electrons · Physics 2022-03-21 Gaopei Pan , Xu Zhang , Heqiu Li , Kai Sun , Zi Yang Meng

Excited conduction electrons, conduction holes, and valence holes in monolayer electron-doped graphene exhibit unusual Coulomb decay rates. The deexcitation processes are studied using the screened exchange energy. They might utilize the…

Mesoscale and Nanoscale Physics · Physics 2019-02-26 Chih-Wei Chiu , Chiun-Yan Lin , Rong-Bin Chen

We investigate the dynamical dielectric function of a monolayer of molybdenum disulfide within the random phase approximation. While in graphene damping of plasmons is caused by interband transitions, due to the large direct band gap in…

Mesoscale and Nanoscale Physics · Physics 2013-08-08 Andreas Scholz , Tobias Stauber , John Schliemann

Spatially varying strained graphene can acquire interesting electronic properties because of the strain-induced valley-dependent gauge (pseudomagnetic) fields1,2. Here we report the realization of strained graphene regions located close to…

Materials Science · Physics 2015-03-31 Jun-Fang Liu , Ke-Ke Bai , Jia-Bin Qiao , Yu Zhou , Jia-Cai Nie , Hailin Peng , Zhongfan Liu , Lin He

Graphene corrugations affect hybridization of $\pi$ and $\sigma$ orbitals of carbon atoms in graphene based systems. It can as well break differently the symmetry of the electron transfer integrals for different strip boundaries. Using…

Mesoscale and Nanoscale Physics · Physics 2024-05-07 M. Pudlak , R. G. Nazmitdinov

We present a theory of superconductivity in twisted bilayer graphene in which attraction is generated between electrons on the same honeycomb sublattice when the system is close to a sublattice polarization instability. The resulting Cooper…

Mesoscale and Nanoscale Physics · Physics 2022-10-26 Chunli Huang , Nemin Wei , Wei Qin , Allan MacDonald

We investigate the plasmon dispersion relation and damping rate of collective excitations in a double-layer system consisting of bilayer graphene and GaAs quantum well, separated by a distance, at zero temperature with no interlayer…

Mesoscale and Nanoscale Physics · Physics 2017-11-22 Nguyen Van Men , Nguyen Quoc Khanh