English
Related papers

Related papers: Designer Topological Insulators in Superlattices

200 papers

We propose the creation of a two-dimensional topological semimetal in a semiconductor artificial lattice with triangular symmetry. An in-plane magnetic field drives a quantum phase transition between the topological insulating and…

Mesoscale and Nanoscale Physics · Physics 2017-08-09 Tommy Li , Oleg P. Sushkov

The newly discovered topological crystalline insulators (TCIs) harbor a complex band structure involving multiple Dirac cones. These materials are potentially highly tunable by external electric field, temperature or strain and could find…

When a charge current is injected into the surface state of a topological insulator (TI), the resulting shift of the spin-momentum-locked Fermi surface leads to the appearance of a net spin polarization. The helical spin structure of the…

Mesoscale and Nanoscale Physics · Physics 2023-12-12 Linh T. Dang , Oliver Breunig , Zhiwei Wang , Henry F. Legg , Yoichi Ando

Topological insulators (TIs) are materials with an insulating bulk characterized by a gapped band structure, along with gapless metallic surface states having a Dirac cone with a helical spin structure in momentum space. The helical…

Materials Science · Physics 2024-09-02 Sumana Paul , Moumita Das , Sujoy Datta , Raja Chakraborty , Prabhat Mandal , P. K. Giri

We study topological phases in Iridium (Ir) oxide superlattices of orthorhombic perovskite-type grown along the [001] crystallographic axis. Due to strong spin-orbit coupling of Ir 5d-orbitals and electronic correlation effects, Ir oxide…

Mesoscale and Nanoscale Physics · Physics 2014-11-26 Yige Chen , Hae-Young Kee

We present an exact solution of a modifed Dirac equation for topological insulator in the presence of a hole or vacancy to demonstrate that vacancies may induce bound states in the band gap of topological insulators. They arise due to the…

Mesoscale and Nanoscale Physics · Physics 2011-07-22 Wen-Yu Shan , Jie Lu , Hai-Zhou Lu , Shun-Qing Shen

We calculate the local density of states of two prototypical topological insulators (Bi$_2$Se$_3$ and Bi$_2$Te$_2$Se) as a function of distance from the surface within density functional theory. We find that, in the absence of disorder or…

Mesoscale and Nanoscale Physics · Physics 2015-10-08 Benjamin M. Fregoso , Sinisa Coh

Topological phases arise from the elegant mathematical structures imposed by the interplay between symmetry and topology1-5. From gapped topological insulators to gapless semimetals, topological materials in both quantum and classical…

The surface of a topological insulator hosts Dirac electronic states with the spin-momentum locking, which constrains spin orientation perpendicular to electron momentum. As a result, collective plasma excitations in the interacting Dirac…

Mesoscale and Nanoscale Physics · Physics 2021-08-18 Dmitry K. Efimkin , Mehdi Kargarian

Topological phases enable protected transport along the edges of materials, offering immunity against scattering from disorder and imperfections. These phases were suggested and demonstrated not only for electronic systems, but also for…

The band inversions that generate the topologically non-trivial band gaps of topological insulators and the isolated Dirac touching points of three-dimensional Dirac semimetals generally arise from the crossings of electronic states derived…

Topological insulators are materials with an insulating bulk interior while maintaining gapless boundary states against back scattering. Bi$_2$Se$_3$ is a prototypical topological insulator with a Dirac-cone surface state around $\Gamma$.…

Surfaces of topological insulators host a new class of states with Dirac dispersion and helical spin texture. Potential quantum computing and spintronic applications using these states require manipulation of their electronic properties at…

Mesoscale and Nanoscale Physics · Physics 2015-05-30 Haim Beidenkopf , Pedram Roushan , Jungpil Seo , Lindsay Gorman , Ilya Drozdov , Yew San Hor , R. J. Cava , Ali Yazdani

We characterize the occupied and unoccupied electronic structure of the topological insulator Bi$_2$Se$_3$ by one-photon and two-photon angle-resolved photoemission spectroscopy and slab band structure calculations. We reveal a second,…

Topologically protected gapless edge states are phases of quantum matter which behave as massless Dirac fermions, immunizing against disorders and continuous perturbations. Recently, a new class of topological insulators (TIs) with…

Mesoscale and Nanoscale Physics · Physics 2019-08-12 Haiyan Fan , Baizhan Xia , Shengjie Zheng , Liang Tong

The recently discovered three dimensional or bulk topological insulators are expected to exhibit exotic quantum phenomena. It is believed that a trivial insulator can be twisted into a topological state by modulating the spin-orbit…

Mesoscale and Nanoscale Physics · Physics 2011-10-24 Su-Yang Xu , Y. Xia , L. A. Wray , D. Qian , Shuang Jia , J. H. Dil , F. Meier , J. Osterwalder , B. Slomski , H. Lin , R. J. Cava , M. Z. Hasan

We outline here how strong light-matter interaction can be used to induce quantum phase transition between normal and topological phases in two-dimensional topological insulators. We consider the case of a HgTe quantum well, in which band…

Mesoscale and Nanoscale Physics · Physics 2017-11-17 Mehedi Hasan , Dmitry Yudin , Ivan Iorsh , Olle Eriksson , Ivan Shelykh

This work explores the topological phase diagram of inverted-band-gap semiconductors under strain and spin-orbit coupling. Using a minimalistic Luttinger Hamiltonian model, we follow the transitions between a 3D topological insulator, a…

Mesoscale and Nanoscale Physics · Physics 2026-05-25 Vitaly N. Golovach , Alexander Khaetskii

Granular conductors form an artificially engineered class of solid state materials wherein the microstructure can be tuned to mimic a wide range of otherwise inaccessible physical systems. At the same time, topological insulators (TIs) have…

Materials Science · Physics 2017-06-05 Abhishek Banerjee , Oindrila Deb , Kunjalata Majhi , R. Ganesan , Diptiman Sen , P. S. Anil Kumar

In the recently discovered topological crystalline insulators (TCIs), topology and crystal symmetry intertwine to create surface states with a unique set of characteristics. Among the theoretical predictions for TCIs is the possibility of…