English
Related papers

Related papers: Bulk and surface properties of SmB6

200 papers

A topological insulator (TI) is an unusual quantum state in which the insulating bulk is topologically distinct from vacuum, resulting in a unique metallic surface that is robust against time-reversal invariant perturbations. These surface…

Strongly Correlated Electrons · Physics 2013-10-28 D. J. Kim , S. Thomas , T. Grant , J. Botimer , Z. Fisk , Jing Xia

We have investigated the surface states of a potential mixed-valent topological insulator SmB$_6$ based on the first principles density functional theory slab band structure analysis. We have found that metallic surface states are formed in…

Strongly Correlated Electrons · Physics 2015-06-19 Junwon Kim , Kyoo Kim , Chang-Jong Kang , Sooran Kim , Hong Chul Choi , J. -S. Kang , J. D. Denlinger , B. I. Min

The spin-polarized surface states of topological insulators have attracted interest both from a fundamental and applied point of view. A recent proposal describes a method of probing these surface states with ferromagnetic contacts, which…

Mesoscale and Nanoscale Physics · Physics 2019-07-29 Johannes Geurs , Gihun Ryu , Chengtian Lin , Jurgen H. Smet

Planar tunneling spectroscopy of the Kondo insulator SmB$_6$ suggests that an interaction between the surface Dirac fermions and the bulk spin excitons results in incompletely protected topological surface states. To gain further insight…

Strongly Correlated Electrons · Physics 2023-05-03 A. Gupta , A. Weiser , L. H. Greene , L. Pressley , Y. Luo , C. Lygouras , J. Trowbridge , W. A. Phelan , C. L. Broholm , T. McQueen , W. K. Park

The topology and spin-orbital polarization of two-dimensional (2D) surface electronic states have been extensively studied in this decade. One major interest in them is their close relationship with the parities of the bulk (3D) electronic…

Strongly Correlated Electrons · Physics 2022-09-27 Yoshiyuki Ohtsubo , Toru Nakaya , Takuto Nakamura , Patrick Le Fèvre , François Bertran , Fumitoshi Iga , Shin-Ichi Kimura

The electronic structures of two mixed valence insulators YbB$_6$ and YbB$_12$ are studied by using the local density approximation (LDA) supplemented with the Gutzwiller method and dynamic mean field theory (DMFT). YbB$_6$ is found to be a…

Strongly Correlated Electrons · Physics 2014-01-20 Hongming Weng , Jianzhou Zhao , Zhijun Wang , Zhong Fang , Xi Dai

Kondo insulators have recently aroused great interest because they are promising materials that host a topological insulator state caused by the strong electron interactions. Moreover, recent observations of the quantum oscillations in the…

Strongly Correlated Electrons · Physics 2021-07-22 Y. Sato , Z. Xiang , Y. Kasahara , S. Kasahara , Lu Chen , C. Tinsman , F. Iga , J. Singleton , N. L. Nair , N. Maksimovic , J. G. Analytis , Lu Li , Y. Matsuda

We present results of resistance fluctuation spectroscopy on single crystals of the predicted Kondo topological insulator material SmB$_6$. Our measurements show that at low temperatures, transport in this system takes place only through…

Mesoscale and Nanoscale Physics · Physics 2017-05-30 Sangram Biswas , M. Ciomaga Hatnean , G. Balakrishnan , Aveek Bid

We present angle-resolved photoemission studies on the rare-earth hexaboride YbB$_6$, which has recently been predicted to be a topological Kondo insulator. Our data do not agree with the prediction and instead show that YbB$_6$ exhibits a…

Whether SmB6 is a topological insulator remains hotly debated. Our density functional theory plus dynamical mean field theory calculations are in excellent agreement with a large range of experiments, from the 4f5.5 intermediate valency to…

Strongly Correlated Electrons · Physics 2021-08-25 Patrik Thunström , Karsten Held

Recent studies suggest that an exemplary Kondo insulator SmB6 belongs to a new class of topological insulators (TIs), in which non-trivial spin-polarized metallic states emerge on surface upon the formation of Kondo hybridization gap in the…

Strongly Correlated Electrons · Physics 2015-07-24 Y. Ishida , T. Otsu , T. Shimada , M. Okawa , Y. Kobayashi , F. Iga , T. Takabatake , S. Shin

SmB6 is a mixed valence Kondo insulator that exhibits a sharp increase in resistance following an activated behavior that levels off and saturates below 4K. This behavior can be explained by the proposal of SmB6 representing a new state of…

Strongly Correlated Electrons · Physics 2018-02-14 Brian Casas , Alex Stern , Dmitry K. Efimkin , Zachary Fisk , Jing Xia

SmB$_6$ exhibits a small (15-20 meV) bandgap at low temperatures due to hybridized $d$ and $f$ electrons, a tiny (3 meV) transport activation energy $(E_{A})$ above 4 K, and surface states accessible to transport below 2 K. We study its…

Strongly Correlated Electrons · Physics 2017-06-21 S. Wolgast , Y. S. Eo , K. Sun , Ç. Kurdak , F. F. Balakirev , M. Jaime , D. -J. Kim , Z. Fisk

Recent quantum oscillation experiments on SmB$_6$ pose a paradox, for while the angular dependence of the oscillation frequencies suggest a 3D bulk Fermi surface, SmB$_6$ remains robustly insulating to very high magnetic fields. Moreover, a…

Strongly Correlated Electrons · Physics 2016-02-02 Onur Erten , Pouyan Ghaemi , Piers Coleman

Heavy-fermion family exhibits fascinating and often puzzling properties due to the presence of open-shell $f$ ions and the complexity of the associated charge, orbital, and spin degrees of freedom. SmB$_6 $ is a prototypical heavy-fermion…

Starting from the kp method in combination with first-principles calculations, we systematically derive the effective Hamiltonians that capture the low energy band structures of recently discovered topological Kondo insulator SmB6. Using…

Materials Science · Physics 2015-02-06 Rui Yu , HongMing Weng , Xiao Hu , Zhong Fang , Xi Dai

This article reviews recent theoretical and experimental work on a new class of topological material - topological Kondo insulators, which develop through the interplay of strong correlations and spin-orbit interactions. The history of…

Strongly Correlated Electrons · Physics 2016-04-20 Maxim Dzero , Jing Xia , Victor Galitski , Piers Coleman

Here we propose the existence of a non-static ground state in the Kondo insulator SmB6, with a unique accompany-type valence fluctuation of Sm ions in its bulk. Whether SmB6 is a fashion of time crystal is an intriguing issue.

Strongly Correlated Electrons · Physics 2017-09-26 Qi Wu , Liling Sun

We address the long-standing mystery of the nonmagnetic insulating state of the intermediate valence compound SmB$_6$. Within a combination of the local density approximation (LDA) and an exact diagonalization (ED) of an effective discrete…

Strongly Correlated Electrons · Physics 2015-10-26 A. B. Shick , L. Havela , A. I. Lichtenstein , M. I. Katsnelson

The concept of a topological Kondo insulator (TKI) has been brought forward as a new class of topological insulators in which non-trivial surface states reside in the bulk Kondo band gap at low temperature due to the strong spin-orbit…