Author(s): Zhonglin He, Rui Peng, Xiangyu Feng, Xilong Xu, Ying Dai, Baibiao Huang, and Yandong Ma
Two-dimensional (2D) valleytronic materials, exhibiting valley-contrasting physics, are both fundamentally intriguing and practically appealing to be used in nanoscale devices. In this work, through first-principles calculations and model analysis, we identify single-layer Cr2Se3 as a promising 2D v...
[Phys. Rev. B 104, 075105] Published Thu Aug 05, 2021
Author(s): Tappei Kawakami, Katsuaki Sugawara, Takemi Kato, Taiki Taguchi, Seigo Souma, Takashi Takahashi, and Takafumi Sato
We have performed angle-resolved photoemission spectroscopy on epitaxial VTe2 films to elucidate the relationship between the fermiology and charge density waves (CDWs). We found that a two-dimensional triangular pocket in 1 monolayer (ML) VTe2 is converted to a strongly warped quasi-one-dimensional...
[Phys. Rev. B 104, 045136] Published Fri Jul 23, 2021
Author(s): Sejoong Kim and Young-Woo Son
We theoretically show that two distinctive spin textures manifest themselves around saddle points in energy bands of monolayer NbSe2 under external gate potentials. While the density of states at all saddle points diverge logarithmically, ones at the zone boundaries display a windmill-shaped spin te...
[Phys. Rev. B 104, 045426] Published Mon Jul 26, 2021
Author(s): Jinling Yu, Hang Zhuang, Kejing Zhu, Yonghai Chen, Yu Liu, Yang Zhang, Chunming Yin, Shuying Cheng, Yunfeng Lai, Ke He, and Qikun Xue
Current-induced spin polarization (CISP) in the topological insulator (TI) Bi2Te3 has been observed via circularly polarized photoconductive differential current (CPDC). It is found that the CPDC induced by the CISP is proportional to the square of the longitudinal electric field when the electric f...
[Phys. Rev. B 104, 045428] Published Tue Jul 27, 2021
Author(s): S. X. M. Riberolles, Q. Zhang, Elijah Gordon, N. P. Butch, Liqin Ke, J.-Q. Yan, and R. J. McQueeney
The Mn(Bi1−xSbx)2Te4 series is purported to span from an antiferromagnetic (AF) topological insulator at x=0 to a trivial AF insulator at x=1. Here we report on neutron diffraction and inelastic neutron scattering studies of the magnetic interactions across this series. All compounds measured posses...
[Phys. Rev. B 104, 064401] Published Mon Aug 02, 2021
Author(s): Lewis S. Hart, Surani M. Gunasekera, Marcin Mucha-Kruczyński, James L. Webb, José Avila, María C. Asensio, and Daniel Wolverson
We study the valence band structure of ReSe2 crystals with varying thickness down to a single layer using nanoscale angle-resolved photoemission spectroscopy and density functional theory. The width of the top valence band in the direction perpendicular to the rhenium chains decreases with decreasin...
[Phys. Rev. B 104, 035421] Published Thu Jul 15, 2021
Author(s): G. Kremer, M. Rumo, C. Yue, A. Pulkkinen, C. W. Nicholson, T. Jaouen, F. O. von Rohr, P. Werner, and C. Monney
Black phosphorus is a quasi-two-dimensional layered semiconductor with a narrow direct band gap of 0.3 eV. A giant surface Stark effect can be produced by the potassium doping of black phosphorus, leading to a semiconductor to semimetal phase transition originating from the creation of a strong surf...
[Phys. Rev. B 104, 035125] Published Mon Jul 12, 2021
Author(s): Chenhui Yan, Sebastian Fernandez-Mulligan, Ruobing Mei, Seng Huat Lee, Nikola Protic, Rikuto Fukumori, Binghai Yan, Chaoxing Liu, Zhiqiang Mao, and Shuolong Yang
Despite the rapid progress in understanding the first intrinsic magnetic topological insulator MnBi2Te4, its electronic structure remains a topic under debates. Here we perform a thorough spectroscopic investigation into the electronic structure of MnBi2Te4 via laser-based angle-resolved photoemissi...
[Phys. Rev. B 104, L041102] Published Tue Jul 06, 2021
Author(s): Chiara Bigi, Federico Mazzola, Jun Fujii, Ivana Vobornik, Giancarlo Panaccione, and Giorgio Rossi
Probing the energy and spin electron properties of materials by means of photoemission spectroscopy gives insights into the low-energy phenomena of matter driven by spin orbit coupling or exchange interaction. The information that can be derived from complete photoelectron spectroscopy experiments, ...
[Phys. Rev. B 103, 245142] Published Fri Jun 25, 2021
Author(s): Raquel Esteban-Puyuelo and Biplab Sanyal
In this paper, we have systematically studied the role of point defects in the recombination time of monolayer MoS2 using time-dependent ab initio nonadiabatic molecular dynamics simulations. Various types of point defects, such as S vacancy, S interstitial, Mo vacancy, and Mo interstitial have been...
[Phys. Rev. B 103, 235433] Published Mon Jun 28, 2021
Author(s): L. M. Sandratskii and K. Carva
Recently discovered ferromagnetism of the layered van der Waals material VI3 attracts much research attention. Despite substantial progress, in the following important aspects no consensus has been reached: (i) a possible deviation of the easy axis from the normal to the VI3 layers, (ii) a possible ...
[Phys. Rev. B 103, 214451] Published Tue Jun 29, 2021
Author(s): Jihang Zhu, Jingtian Shi, and Allan H. MacDonald
Graphene-based moiré superlattices are now established as an interesting platform for strongly correlated many-electron physics, and they have so far been characterized mainly by transport and scanning tunneling microscopy (STM) measurements. Motivated by recent experimental progress, we present a t...
[Phys. Rev. B 103, 235146] Published Tue Jun 22, 2021
Klara VolckaertWoohoo!
Author(s): Paulina Majchrzak, Sahar Pakdel, Deepnarayan Biswas, Alfred J. H. Jones, Klara Volckaert, Igor Marković, Federico Andreatta, Raman Sankar, Chris Jozwiak, Eli Rotenberg, Aaron Bostwick, Charlotte E. Sanders, Yu Zhang, Gabriel Karras, Richard T. Chapman, Adam Wyatt, Emma Springate, Jill A. Miwa, Philip Hofmann, Phil D. C. King, Nicola Lanatà, Young Jun Chang, and Søren Ulstrup
We apply an intense infrared laser pulse in order to perturb the electronic and vibrational states in the three-dimensional charge density wave material 1T−VSe2. Ultrafast snapshots of the light-induced hot carrier dynamics and nonequilibrium quasiparticle spectral function are collected using time-...
[Phys. Rev. B 103, L241108] Published Wed Jun 16, 2021
Author(s): Dan Nevola, Alexander Bataller, Ankit Kumar, Samanvitha Sridhar, Jordan Frick, Shaun O'Donnell, Harald Ade, Paul A. Maggard, Alexander F. Kemper, Kenan Gundogdu, and Daniel B. Dougherty
The nonequilibrium properties of strongly correlated materials present a target in the search for new phases of matter. It is important to observe the types of excitations that exist in these materials and their associated relaxation dynamics. We have studied the photoexcitations in a spin-orbit ass...
[Phys. Rev. B 103, 245105] Published Tue Jun 01, 2021
Author(s): Hongtao Rong, Liqin Zhou, Junbao He, Chunyao Song, Jianwei Huang, Cheng Hu, Yu Xu, Yongqing Cai, Hao Chen, Cong Li, Qingyan Wang, Lin Zhao, Zhihai Zhu, Guodong Liu, Zuyan Xu, Genfu Chen, Hongming Weng, and X. J. Zhou
We have carried out detailed high-resolution angle-resolved photoemission spectroscopy measurements and band structure calculations to study the electronic structure of CaMnSb2. The observed Fermi surface mainly consists of one hole pocket around the Γ point and one tiny hole pocket at the Y point. ...
[Phys. Rev. B 103, 245104] Published Tue Jun 01, 2021
Author(s): G. Stefanucci and E. Perfetto
We calculate the exact time-resolved ARPES spectrum of a two-band model semiconductor driven out of equilibrium by resonant and nonresonant laser pulses, highlighting the effects of phonon-induced decoherence and relaxation. Resonant excitations initially yield a replica of the valence band shifted ...
[Phys. Rev. B 103, 245103] Published Tue Jun 01, 2021
Author(s): Yulei Han, Shiyang Sun, Shifei Qi, Xiaohong Xu, and Zhenhua Qiao
The interlayer antiferromagnetic coupling hinders the observation of quantum anomalous Hall effect in magnetic topological insulator MnBi2Te4. We demonstrate that interlayer ferromagnetism can be established by utilizing the p-doping method in MnBi2Te4 multilayers. In two septuple layers system, the...
[Phys. Rev. B 103, 245403] Published Wed Jun 02, 2021
Author(s): E. Perfetto and G. Stefanucci
We show the formation of a nonequilibrium excitonic condensate in a bulk WSe2 coherently pumped in resonance with the lowest-energy exciton. The lifetime of the superfluid is addressed by studying the screened dynamics during and after the pump pulse. Intervalley scattering causes electron migration...
[Phys. Rev. B 103, L241404] Published Mon Jun 07, 2021
Author(s): D. Y. Yan, M. Yang, P. B. Song, Y. T. Song, C. X. Wang, C. J. Yi, and Y. G. Shi
MnSb2Te4 has been proposed to have magnetic topological states as a potential Weyl semimetal. We synthesized single crystals of MnSb2Te4 and systematically investigated their structural and physical properties. MnSb2Te4 has an isostructural septuple-layered structure that is similar to the magnetic ...
[Phys. Rev. B 103, 224412] Published Wed Jun 09, 2021
Author(s): L. X. Xu, Y. Y. Y. Xia, S. Liu, Y. W. Li, L.Y. Wei, H. Y. Wang, C. W. Wang, H. F. Yang, A. J. Liang, K. Huang, T. Deng, W. Xia, X. Zhang, H. J. Zheng, Y. J. Chen, L. X. Yang, M. X. Wang, Y. F. Guo, G. Li, Z. K. Liu, and Y. L. Chen
Topological materials host fascinating low dimensional gapless states at the boundary. As a prominent example, helical topological edge states (TESs) of two-dimensional topological insulators and their stacked three-dimensional equivalent, weak topological insulators (WTIs), have sparked research en...
[Phys. Rev. B 103, L201109] Published Thu May 13, 2021
Author(s): Michele Pisarra, Cristina Díaz, and Fernando Martín
Computational physics and chemistry are called to play a very important role in the development of new technologies based on two-dimensional (2D) materials, reducing drastically the number of trial and error experiments needed to obtain meaningful advances in the field. Here, we present a thorough t...
[Phys. Rev. B 103, 195416] Published Thu May 13, 2021
Author(s): Samuel W. Teitelbaum, Thomas C. Henighan, Hanzhe Liu, Mason P. Jiang, Diling Zhu, Matthieu Chollet, Takahiro Sato, Éamonn D. Murray, Stephen Fahy, Shane O'Mahony, Trevor P. Bailey, Ctirad Uher, Mariano Trigo, and David A. Reis
We demonstrate an experimental approach to determining the excited-state interatomic forces using femtosecond x-ray pulses from an x-ray free-electron laser. We determine experimentally the excited-state interatomic forces that connect photoexcited carriers to the nonequilibrium lattice dynamics in ...
[Phys. Rev. B 103, L180101] Published Tue May 18, 2021
Author(s): T. K. Kim, K. S. Pervakov, D. V. Evtushinsky, S. W. Jung, G. Poelchen, K. Kummer, V. A. Vlasenko, A. V. Sadakov, A. S. Usoltsev, V. M. Pudalov, D. Roditchev, V. S. Stolyarov, D. V. Vyalikh, V. Borisov, R. Valentí, A. Ernst, S. V. Eremeev, and E. V. Chulkov
In the novel stoichiometric iron-based material RbEuFe4As4, superconductivity coexists with a peculiar long-range magnetic order of Eu 4f states. Using angle-resolved photoemission spectroscopy, we reveal a complex three-dimensional electronic structure and compare it with density functional theory ...
[Phys. Rev. B 103, 174517] Published Tue May 25, 2021
Author(s): Fabio Caruso, Patrick Amsalem, Jie Ma, Areej Aljarb, Thorsten Schultz, Marios Zacharias, Vincent Tung, Norbert Koch, and Claudia Draxl
We report experimental and theoretical evidence of strong electron-plasmon interaction in n-doped single-layer MoS2. Angle-resolved photoemission spectroscopy measurements reveal the emergence of distinctive signatures of polaronic coupling in the electron spectral function. Calculations based on ma...
[Phys. Rev. B 103, 205152] Published Thu May 27, 2021
Author(s): Kirstine Junker Dalgaard, Simone Munkholm Kevy, Laura Wollesen, Qing Ma, Steffen Wiedmann, Kajsa G. V. Sigfridsson Clauss, and Martin Bremholm
In the prospect of realizing bulk superconductivity in a topological insulator, metal-doped Bi2Se3 has been investigated with increased interest, where the Cu-, Sr-, and Nb-doped systems appear particularly promising. It is generally assumed that metal intercalation into the van der Waals (vdW) gap ...
[Phys. Rev. B 103, 184103] Published Fri May 07, 2021
Author(s): Dino Novko, Vito Despoja, Marcel Reutzel, Andi Li, Hrvoje Petek, and Branko Gumhalter
Recent two-photon photoemission studies of silver have demonstrated that the energies of certain spectral lines do not exhibit Einstein’s linear scaling with the photon energy but stay pinned at double the plasmon energy above the Fermi level. Here, a theory of this peculiar effect is presented based on plasmonically assisted channels of photoemission, in which real plasmons excited in secondary processes act as excitation field for emitting electrons from the Fermi level at multiples of the plasmon energy. This reveals non−Einsteinianchannelsofphotoemission from metals.
[Phys. Rev. B 103, 205401] Published Mon May 03, 2021
Author(s): T. Fukasawa, S. Kusaka, K. Sumida, M. Hashizume, S. Ichinokura, Y. Takeda, S. Ideta, K. Tanaka, R. Shimizu, T. Hitosugi, and T. Hirahara
We successfully fabricated a MnBi2Te4/Bi2Te3 heterostructure by incorporating Mn and Te inside the topmost quintuple layer of Bi2Te3, as unambiguously confirmed by low-energy electron diffraction I−V and scanning transmission electron microscopy measurements. The surface-state Dirac cone of the hete...
[Phys. Rev. B 103, 205405] Published Tue May 04, 2021
Author(s): Ankit Arora, Pramoda K. Nayak, Swastibrata Bhattacharyya, Nikhilesh Maity, Abhishek K. Singh, Ananth Krishnan, and M. S. Ramachandra Rao
In the present work, we report different interlayer excitonic states of an aligned MoSe2/MoS2 incommensurate van der Waals (vdW) heterostructure (HS). The HS was fabricated by stacking chemical vapor deposited monolayers, and it was studied using photoluminescence (PL) measurements. We observed the ...
[Phys. Rev. B 103, 205406] Published Wed May 05, 2021
Author(s): J. D. Verbakel, Q. Yao, K. Sotthewes, and H. J. W. Zandvliet
In twisted bilayer graphene at small twist angles, the application of an electric field can break the inversion symmetry between AB- and BA-stacked domains. This causes a network of one-dimensional topologically protected states to emerge in the material, which can transport current without dissipation as long as intervalley scattering is absent, according to theoretical predictions. In this work, using atomic-resolution STM images of the network taken at room temperature, the authors show that the topological network is indeed valley protected.
[Phys. Rev. B 103, 165134] Published Fri Apr 23, 2021
Author(s): P. Moras, T. O. Menteş, F. Schiller, L. Ferrari, D. Topwal, A. Locatelli, P. M. Sheverdyaeva, and C. Carbone
During the photoemission process the parallel component of the photoelectron momentum is conserved across the modulation plane of the wavefunction, which is the so-called reference plane. The identification of this plane is straightforward for low Miller-index surfaces, but questionable for surfaces of lower symmetry. In this work, the authors show experimentally the coexistence of two different reference planes for surface and bulklike quantum-well states of thin nanostructured films grown on a regularly stepped substrate.
[Phys. Rev. B 103, 165426] Published Tue Apr 27, 2021