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Related papers: Persistent Dirac Fermion State on Bulk-like Si(111…

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Topological semimetals materialize a new state of quantum matter where massless fermions protected by a specific crystal symmetry host exotic quantum phenomena. Distinct from well-known Dirac and Weyl fermions, structurally-chiral…

A silicene-like polymorph of the Si111 7x7 surface is proposed that resolves numerous experimental paradoxes and inconsistencies arising over the past 34 years. An analysis of the three established surface state charge densities from atom…

Materials Science · Physics 2019-05-30 J. E. Demuth

Using a gold (111) surface as a substrate we have grown in situ by molecular beam epitaxy an atom-thin, ordered, two-dimensional multi-phase film. Its growth bears strong similarity with the formation of silicene layers on silver (111)…

Materials Science · Physics 2015-06-19 M. E. Dávila , L. Xian , S. Cahangirov , A. Rubio , G. Le Lay

In the presence of certain symmetries, three-dimensional Dirac semimetals can harbor not only surface Fermi arcs, but also surface Dirac cones. Motivated by the experimental observation of rotation-symmetry-protected Dirac semimetal states…

Superconductivity · Physics 2022-01-17 Majid Kheirkhah , Zheng-Yang Zhuang , Joseph Maciejko , Zhongbo Yan

The electromagnetic interaction between Ag nanoparticles on the top of the Si substrate and the incident light has been studied by numerical simulations. It is found that the presence of a dielectric layer with different thickness leads to…

Materials Science · Physics 2011-09-22 Xu Rui , Wang Xiao-Dong , Liu Wen , Xu Xiao-Na , Li Yue-Qiang , Ji An , Yang Fu-Hua , Li Jin-Min

Ultrathin films of Na3Bi on insulating substrates are desired for opening a bulk band gap and generating the quantum spin Hall effect from a topological Dirac semimetal, though continuous films in the few nanometer regime have been…

Despite its interest for CMOS applications, Atomic Layer Deposition (ALD) of GeO$_{2}$ thin films, by itself or in combination with SiO$_{2}$, has not been widely investigated yet. Here we report the ALD growth of SiO$_{2}$/GeO$_{2}$…

Materials Science · Physics 2020-07-29 Jordi Antoja-Lleonart , Silang Zhou , Kit de Hond , Gertjan Koster , Guus Rijnders , Beatriz Noheda

Dirac and Weyl semimetals both exhibit arc-like surface states. However, whereas the surface Fermi arcs in Weyl semimetals are topological consequences of the Weyl points themselves, the surface Fermi arcs in Dirac semimetals are not…

Mesoscale and Nanoscale Physics · Physics 2023-09-27 Benjamin J. Wieder , Zhijun Wang , Jennifer Cano , Xi Dai , Leslie M. Schoop , Barry Bradlyn , B. Andrei Bernevig

The massless Dirac fermions residing on the surface of three-dimensional topological insulators are protected from backscattering and cannot be localized by disorder, but such protection can be lifted in ultrathin films when the…

Mesoscale and Nanoscale Physics · Physics 2015-06-04 A. A. Taskin , Satoshi Sasaki , Kouji Segawa , Yoichi Ando

In this work, we report our results on the geometric and electronic properties of hybrid graphite-like structure made up of silicene and boron nitride (BN) layers. We predict from our calculations that this hybrid bulk system, with…

Materials Science · Physics 2015-02-26 C. Kamal , Aparna Chakrabarti , Arup Banerjee

Using an evolutionary algorithm in combination with first-principles density functional theory calculations, we identify two-dimensional (2D) CaP$_3$ monolayer as a new Dirac semimetal due to inversion and nonsymmorphic spatial symmetries…

Materials Science · Physics 2023-03-06 Seoung-Hun Kang , Wei Luo , Sinchul Yeom , Yaling Zheng , Mina Yoon

In-plane compressively strained $\alpha$-Sn films have been theoretically predicted and experimentally proven to possess non-trivial electronic states of a 3D topological Dirac semimetal. The robustness of these states typically strongly…

The newly observed ($\sqrt3$$\times$$\sqrt3$) surface reconstruction in heteroepitaxial Si(111) thin films on metal substrates is widely considered as a promising platform to realize 2D Dirac and topological states, yet its formation…

Materials Science · Physics 2017-06-21 Wei Jiang , Zheng Liu , Miao Zhou , Xiaojuan Ni , Feng Liu

In a slab geometry with large surface-to-bulk ratio, topological surface states such as Fermi arcs for Weyl or Dirac semimetals may dominate their low-energy properties. We investigate the collective charge oscillations in such systems,…

Mesoscale and Nanoscale Physics · Physics 2023-08-10 Debasmita Giri , Dibya Kanti Mukherjee , Sonu Verma , H. A. Fertig , Arijit Kundu

In a vicinity of the Fermi surface, graphene layers with bandgaps allow for closely simulating the vacuum of quantum electrodynamics and, thus, its yet unverified strong-field phenomenology with accessible field strengths. This striking…

Mesoscale and Nanoscale Physics · Physics 2019-02-06 Ibrahim Akal , Reinhold Egger , Carsten Müller , Selym Villalba-Chávez

In a Dirac semimetal, the massless Dirac fermion has zero chirality, leading to surface states connected adiabatically to a topologically trivial surface state as well as vanishing anomalous Hall effect (AHE). Recently, it is predicted that…

We studied the behavior of nontrivial Dirac fermion states in an antiferromagnetic metal SmBi using angle-resolved photoemission spectroscopy (ARPES). The experimental results exhibit multiple Fermi pockets around $\overline{\Gamma}$ and…

The signatures of topological superconductivity (TSC) in the superconducting materials with topological nontrivial states prompt intensive researches recently. Utilizing high-resolution angle-resolved photoemission spectroscopy and…

Transition metal aluminum nitrides are a technologically important class of multifunctional ceramics, however, the HfAlN system remains largely unexplored. We investigate phase stability, nanostructure design, and mechanical behavior of…

Strong Coulomb repulsion is predicted to open a many-body charge gap at the Dirac point of graphene, transforming the semimetal into a Mott insulator. However, this correlated insulating phase has remained inaccessible in pristine graphene,…