Author(s): Ping Li, Jiangying Yu, Ying Wang, and Weidong Luo
First-principles calculations are performed to study the electronic structures and topological phases of magnetic layered materials MnBi2Te4, MnBi2Se4, and MnSb2Te4 under different film thicknesses, strains, and spin-orbit coupling (SOC) strengths. All these compounds energetically prefer the antife...
[Phys. Rev. B 103, 155118] Published Fri Apr 09, 2021
Author(s): M. Zonno, F. Boschini, E. Razzoli, S. K. Y. Dufresne, M. Michiardi, M. X. Na, T. M. Pedersen, S. Gorovikov, S. Gonzalez, G. Di Santo, L. Petaccia, M. Schneider, D. Wong, P. Dosanjh, Y. Yoshida, H. Eisaki, R. D. Zhong, J. A. Schneeloch, G. D. Gu, A. K. Mills, S. Zhdanovich, G. Levy, D. J. Jones, and A. Damascelli
High-temperature superconducting cuprates exhibit an intriguing phenomenology for the low-energy elementary excitations. In particular, an unconventional temperature dependence of the coherent spectral weight (CSW) has been observed in the superconducting phase by angle-resolved photoemission spectr...
[Phys. Rev. B 103, 155109] Published Wed Apr 07, 2021
Author(s): Zakariae El Youbi, Sung Won Jung, Christine Richter, Karol Hricovini, Cephise Cacho, and Matthew D. Watson
We investigate the electronic structure of the 2H and 3R polytypes of NbS2. The Fermi surfaces measured by angle-resolved photoemission spectroscopy show a remarkable difference in size, reflecting a significantly increased band filling in 3R−Nb1+xS2 compared to 2H−NbS2, which we attribute to the pr...
[Phys. Rev. B 103, 155105] Published Fri Apr 02, 2021
Author(s): Xiao-Ming Ma et al.
Intrinsic magnetic topological insulators, exemplified by MnBi2Te4, receive considerable research interest, due to the potential quantum anomalous Hall state and axion insulator phase at higher temperatures. Opening up an energy gap at the topological surface state is crucial for the realization of these effects. Here, the authors utilize systematic ARPES data to show that a gapped Dirac cone can be realized in Sb-doped MnBi2Te4. This gap remains immune regardless of the magnetic phase of the bulk system, while it increases monotonically with the density of Sb dopants.
[Phys. Rev. B 103, L121112] Published Wed Mar 17, 2021
Author(s): Huisheng Zhang, Wenjia Yang, Yingying Wang, and Xiaohong Xu
The recently discovered magnetic topological insulator of MnBi2Te4, has been successfully used to explore emerging physical phenomena, such as the quantum anomalous Hall effect (QAHE) and axion insulator state. Based on first-principles calculations, we have systematically investigated the electroni...
[Phys. Rev. B 103, 094433] Published Mon Mar 22, 2021
Author(s): J. Falke, C. F. Chang, C. E. Liu, D. Takegami, A. Melendez-Sans, C.-S. Chen, L. Zhao, A. C. Komarek, C.-Y. Kuo, C. T. Chen, and L. H. Tjeng
ReO3 is a remarkable transition metal oxide in that it has the highest conductivity of all oxides, comparable even with that of silver. Using state of the art bulk-sensitive angle-resolved photoelectron spectroscopy, the authors are able to observe clear dispersions of the Re 5d and O 2p derived bands as well as the momentum splitting of the Fermi surface due to the Re 5d spin-orbit interaction. The experimental results are compared quantitatively to density functional theory band structure calculations, thereby providing a deeper understanding of the material class of the 5d oxides.
[Phys. Rev. B 103, 115125] Published Mon Mar 15, 2021
Author(s): Takeshi Suzuki, Yasushi Shinohara, Yangfan Lu, Mari Watanabe, Jiadi Xu, Kenichi L. Ishikawa, Hide Takagi, Minoru Nohara, Naoyuki Katayama, Hiroshi Sawa, Masami Fujisawa, Teruto Kanai, Jiro Itatani, Takashi Mizokawa, Shik Shin, and Kozo Okazaki
Photoinduced phase transitions have been intensively studied owing to their promising potential for next-generation devices. Here, the authors develop a novel analysis method: the so-called frequency-domain ARPES (FDARPES). They extend a well established measurement method of time-domain ARPES to detect how electrons are interacting with phonons during the photoinduced insulator-to-metal transition for Ta2NiSe5. They successfully unravel the underlying nature of the photoinduced phase transition. This method has general applicability to other photoinduced phase transitions, including photoinduced magnetism or superconductivity.
[Phys. Rev. B 103, L121105] Published Wed Mar 10, 2021
Author(s): H. H. Wang, X. G. Luo, M. Z. Shi, K. L. Peng, B. Lei, J. H. Cui, D. H. Ma, W. Z. Zhuo, J. J. Ying, Z. Y. Wang, and X. H. Chen
MnBi2Te4 has attracted tremendous interest as the first discovered intrinsic magnetic topological insulator. Due to its heavily n-doped nature, hole doping is required to isolate the effects of the topological states from the bulk, which is necessary for further electronic applications. Here, we sys...
[Phys. Rev. B 103, 085126] Published Thu Feb 18, 2021
Author(s): Shuang-Xing Zhu, Chen Zhang, Qi-Yi Wu, Xiao-Fang Tang, Hao Liu, Zi-Teng Liu, Yang Luo, Jiao-Jiao Song, Fan-Ying Wu, Yin-Zou Zhao, Shu-Yu Liu, Tian Le, Xin Lu, He Ma, Kai-Hui Liu, Ya-Hua Yuan, Han Huang, Jun He, H. Y. Liu, Yu-Xia Duan, and Jian-Qiao Meng
High-resolution angle-resolved photoemission spectroscopy and ultrafast optical pump-probe spectroscopy were used to study semimetallic 1T−TiTe2 quasiparticle dispersion and dynamics. A kink and a flat band, having the same energy scale and temperature-dependent behaviors along the Γ¯−M¯ direction, ...
[Phys. Rev. B 103, 115108] Published Thu Mar 04, 2021
Author(s): Jing-Yang You, Xue-Juan Dong, Bo Gu, and Gang Su
Tuning the topological and magnetic properties of materials by applying an electric field is widely used in spintronics. In this work, we find a topological phase transition from topologically trivial to nontrivial states at an external electric field of about 0.1 V/Å in a MnBi2Te4 monolayer that is...
[Phys. Rev. B 103, 104403] Published Mon Mar 01, 2021
Author(s): Bing Xu, Y. Zhang, E. H. Alizade, Z. A. Jahangirli, F. Lyzwa, E. Sheveleva, P. Marsik, Y. K. Li, Y. G. Yao, Z. W. Wang, B. Shen, Y. M. Dai, V. Kataev, M. M. Otrokov, E. V. Chulkov, N. T. Mamedov, and C. Bernhard
With infrared spectroscopy, we studied the bulk electronic properties of the topological antiferromagnet MnBi2Te4 with TN≃25K. With the support of band-structure calculations, we assign the intra- and interband excitations and determine the band gap of Eg≈0.17 eV. We also obtain evidence for two typ...
[Phys. Rev. B 103, L121103] Published Wed Mar 03, 2021
Author(s): Umut Kamber, Sahar Pakdel, Raluca-Maria Stan, Anand Kamlapure, Brian Kiraly, Fabian Arnold, Andreas Eich, Arlette S. Ngankeu, Marco Bianchi, Jill A. Miwa, Charlotte E. Sanders, Nicola Lanatà, Philip Hofmann, and Alexander A. Khajetoorians
There is immense interest in how the local environment influences the electronic structure of materials at the single-layer limit. We characterize moiré induced spatial variations in the electronic structure of in situ grown monolayer V2S3 on Au(111) by means of low-temperature scanning tunneling mi...
[Phys. Rev. B 103, 115414] Published Tue Mar 09, 2021
Klara VolckaertCongratulations everyone :)
Author(s): Simone M. Kevy, Henriette E. Lund, Laura Wollesen, Kirstine J. Dalgaard, Yu-Te Hsu, Steffen Wiedmann, Marco Bianchi, Ann Julie Utne Holt, Davide Curcio, Deepnarayan Biswas, Alfred J. H. Jones, Klara Volckaert, Cephise Cacho, Pavel Dudin, Philip Hofmann, and Martin Bremholm
The crystal structure, electronic structure, and transport properties of crystals with the nominal composition Nb0.25Bi2Se3 are investigated. X-ray diffraction reveals that the as-grown crystals display phase segregation and contain major contributions of BiSe and the superconducting misfit layer co...
[Phys. Rev. B 103, 085107] Published Fri Feb 05, 2021
Author(s): Anna S. Ketterl, Beatrice Andres, Marco Polverigiani, Vladimir Voroshnin, Cornelius Gahl, Konstantin A. Kokh, Oleg E. Tereshchenko, Evgueni V. Chulkov, Alexander Shikin, and Martin Weinelt
Narrow-gap semiconductors with strong spin-orbit coupling such as bismuth tellurohalides have become popular candidates for spintronic applications. But driving spin-polarized photocurrents in these materials with circularly polarized light requires picosecond lifetimes of the photoexcited carriers ...
[Phys. Rev. B 103, 085406] Published Wed Feb 03, 2021
Author(s): S. Chernov, C. Lidig, O. Fedchenko, K. Medjanik, S. Babenkov, D. Vasilyev, M. Jourdan, G. Schönhense, and H. J. Elmers
Half-metallic ferromagnetic Heusler compounds represent an important class of materials for spintronic applications. We experimentally observe the dispersion of electronic bands with spin resolution in three representative Heusler compounds (Co2MnGa, Co2MnSi, and Co2Fe0.4Mn0.6Si). Bulk-sensitive mea...
[Phys. Rev. B 103, 054407] Published Wed Feb 03, 2021
Author(s): Tim Völzer, Franziska Fennel, Tobias Korn, and Stefan Lochbrunner
Transition-metal dichalcogenides are characterized by a layered lattice structure, facilitating the fabrication of two-dimensional crystals. Concerning their electronic properties, these monolayers differ fundamentally from the bulk material, exhibiting direct band gaps and significantly higher exci...
[Phys. Rev. B 103, 045423] Published Wed Jan 20, 2021
Author(s): Sangwan Sim, Ho-Seung Shin, Doeon Lee, Jekwan Lee, Myungjun Cha, Kyusang Lee, and Hyunyong Choi
The optical and optoelectronic properties of two-dimensional (2D) semiconductors are dominated by excitons, which usually appear as well-defined peaks in the spectral domain. Thus, detailed behaviors of excitons can be understood by tracking transient changes of the fundamental spectral observables,...
[Phys. Rev. B 103, 014309] Published Thu Jan 21, 2021
Author(s): J. A. Crosse and Pilkyung Moon
Twisted bilayer graphene with a twist angle 30° is mapped onto a quasicrystal with a 12-fold rotational symmetry. The authors investigate the quasicrystalline electronic states for every possible two-dimensional twisted bilayer quasicrystal system. The quasicrystalline resonant interaction emerges at specific wave vectors from the combination of the rotational symmetry of the bilayers and the translational symmetries of the constituent layers, as long as all the dominant interlayer interactions occur between the atomic orbitals that have the same magnetic quantum number. In addition, the authors investigate the effects of lifting both interlayer and sublattice symmetry on the respective electronic structures.
[Phys. Rev. B 103, 045408] Published Mon Jan 11, 2021
Author(s): Fabio Bussolotti, Jing Yang, Hiroyo Kawai, Jing Yee Chee, and Kuan Eng Johnson Goh
Monolayer (ML) transition metal dichalcogenides (TMDCs) emerged as ideal materials to combine spin and momentum of charge carriers for spintronics and valleytronics applications. Despite its relevance for TMDC-based technology, the impact of the various many-body-like interactions of charge carriers...
[Phys. Rev. B 103, 045412] Published Wed Jan 13, 2021
Author(s): F. Bisti, F. Priante, A. V. Fedorov, M. Donarelli, M. Fantasia, L. Petaccia, O. Frank, M. Kalbac, G. Profeta, A. Grüneis, and L. Ottaviano
The π*-band renormalization of Li-doped quasifreestanding graphene has been investigated by means of isotope (C13) substitution and angle-resolved photoemission spectroscopy. The well documented sudden slope change (known as “kink”) located at 169 meV from the Fermi level in the graphene made of C12...
[Phys. Rev. B 103, 035119] Published Thu Jan 14, 2021
Author(s): Francis H. Davies, Conor J. Price, Ned T. Taylor, Shane G. Davies, and Steven P. Hepplestone
Two-dimensional heterostructures and superlattices consisting of transition metal dichalcogenides offer huge potential in the next generation of optoelectronic devices. For such transition metal dichalcogenides, a predictive theory of their properties, based upon in-depth understanding of the interl...
[Phys. Rev. B 103, 045417] Published Fri Jan 15, 2021
Author(s): Xiao-Ming Ma et al.
The Mn-Bi-Te family of materials hold promise for realizing the quantum anomalous Hall effect, provided that the topological surface states are gapped by magnetic order. However, previous ARPES measurements have revealed gapless surface Dirac cones for all Mn-Bi-Te antiferromagnetic members. Here, combining ARPES, DFT and tight-binding simulations, the authors find out that the gapless surface Dirac cones result from hybridization between surface and bulk states. This hybridization gives the surface states bulk distribution, with much reduced effective magnetic moment, and thus not sensitive to antiferromagnetic order.
[Phys. Rev. B 102, 245136] Published Tue Dec 22, 2020
Author(s): Hai-Peng Sun, C. M. Wang, Song-Bo Zhang, Rui Chen, Yue Zhao, Chang Liu, Qihang Liu, Chaoyu Chen, Hai-Zhou Lu, and X. C. Xie
Recently, the intrinsic magnetic topological insulator MnBi2Te4 has attracted great attention. It has an out-of-plane antiferromagnetic order, which is believed to open a sizable energy gap in the surface states. This gap, however, was not always observable in the latest angle-resolved photoemission...
[Phys. Rev. B 102, 241406(R)] Published Mon Dec 14, 2020
Author(s): Yipei Zhang, Zhen Zhan, Francisco Guinea, Jose Ángel Silva-Guillén, and Shengjun Yuan
In the emerging world of twisted bilayer structures, the possible configurations are limitless, which enables a rich landscape of electronic properties. In this paper, we focus on twisted bilayer transition metal dichalcogenides (TMDCs) and study their properties by means of an accurate tight-bindin...
[Phys. Rev. B 102, 235418] Published Mon Dec 14, 2020
Author(s): Vassilios Vargiamidis, P. Vasilopoulos, M. Tahir, and Neophytos Neophytou
A valley-contrasting Berry curvature in bilayer transition metal dichalcogenides with spin-orbit coupling can generate valley magnetization when the inversion symmetry is broken, for example, by an electric field, regardless of time-reversal symmetry. A nontrivial Berry curvature can also lead to an...
[Phys. Rev. B 102, 235426] Published Mon Dec 21, 2020
Author(s): Debarchan Das, K. Kobayashi, M. P. Smylie, C. Mielke, III, T. Takahashi, K. Willa, J.-X. Yin, U. Welp, M. Z. Hasan, A. Amato, H. Luetkens, and Z. Guguchia
Recently, the niobium (Nb) doped topological insulator Bi2Se3, in which the finite magnetic moments of the Nb atoms are intercalated in the van der Waals gap between the Bi2Se3 layers, has been shown to exhibit both superconductivity with Tc≃3 K and topological surface states. Here we report on muon...
[Phys. Rev. B 102, 134514] Published Thu Oct 29, 2020
Author(s): Ryan Plumadore, Mehmet Baskurt, Justin Boddison-Chouinard, Gregory Lopinski, Mohsen Modarresi, Pawel Potasz, Pawel Hawrylak, Hasan Sahin, Francois M. Peeters, and Adina Luican-Mayer
Atomic scale defects in semiconductors enable their technological applications and realization of different quantum states. Using scanning tunneling microscopy and spectroscopy complemented by ab initio calculations we determine the nature of defects in the anisotropic van der Waals layered semicond...
[Phys. Rev. B 102, 205408] Published Mon Nov 09, 2020
Author(s): Sumanti Patra, Poonam Kumari, and Priya Mahadevan
In this work we examine the evolution of the electronic structure in twisted bilayers of MoSe2, assuming the moiré potential to be a small perturbation to the untwisted limit. Its role in modifying the electronic structure is probed by mapping the calculated band structure for the moiré cell onto th...
[Phys. Rev. B 102, 205415] Published Thu Nov 12, 2020
Author(s): Alexis Chacón, Dasol Kim, Wei Zhu, Shane P. Kelly, Alexandre Dauphin, Emilio Pisanty, Andrew S. Maxwell, Antonio Picón, Marcelo F. Ciappina, Dong Eon Kim, Christopher Ticknor, Avadh Saxena, and Maciej Lewenstein
The future technological revolution in the production of ultrafast devices lies in the control of materials that will speed-up transistors. The recent discovery of topological states of matter promises a unique opportunity to address this challenge. However, the control and diagnostics of topological materials remain hard to achieve. Here, the authors show an alternative to distinguish a topological phase by its nonlinear-light circular dichroism (CD): the asymmetry of the material-light emissivity while the topological phase is subjected to right-circularly (RCP) and left-circularly polarized (LCP) mid-infrared lasers. This CD exhibits striking distinction in a topological phase, as depicted in the schematic.
[Phys. Rev. B 102, 134115] Published Wed Oct 21, 2020
Author(s): M. Köpf, J. Ebad-Allah, S. H. Lee, Z. Q. Mao, and C. A. Kuntscher
The layered topological insulator MnBi2Te4 has attracted great interest recently due to its intrinsic antiferromagnetic order, potentially hosting various topological phases. By temperature-dependent infrared spectroscopy over a broad frequency range, we studied the changes in the optical conductivi...
[Phys. Rev. B 102, 165139] Published Wed Oct 21, 2020