Klara Volckaert

Author(s): Wei Tao, Zheng Jue Tong, Anirban Das, Duc-Quan Ho, Yudai Sato, Masahiro Haze, Junxiang Jia, Yande Que, Fabio Bussolotti, K. E. Johnson Goh, BaoKai Wang, Hsin Lin, Arun Bansil, Shantanu Mukherjee, Yukio Hasegawa, and Bent Weber

The interplay of topology and superconductivity has become a subject of intense research in condensed-matter physics for the pursuit of topologically nontrivial forms of superconducting pairing. An intrinsically normal-conducting material can inherit superconductivity via electrical contact to a par...

[Phys. Rev. B 105, 094512] Published Thu Mar 24, 2022

Author(s): Julia Amann, Tobias Völkl, Tobias Rockinger, Denis Kochan, Kenji Watanabe, Takashi Taniguchi, Jaroslav Fabian, Dieter Weiss, and Jonathan Eroms

Theory recently predicted that the strength of spin-orbit coupling in bilayer graphene, touching on one side a transition metal dichalcogenide layer such as WSe2, can be tuned easily by moderate gate voltages. Here, the authors show in both theory and experiment that, while spin-orbit splitting of the band structure is a monotonic function of the applied electric field, the visibility of weak antilocalization, a measure of the spin-orbit coupling strength, follows a largely opposite, and nonmonotonic trend.

[Phys. Rev. B 105, 115425] Published Thu Mar 24, 2022

Author(s): Shi Xiao, Xiaoliang Xiao, Fangyang Zhan, Jing Fan, Xiaozhi Wu, and Rui Wang

Applying electric or magnetic fields is widely used to not only create and manipulate topological states but also facilitate their observations in experiments. In this paper, we show by first-principles calculations and topological analysis that the time-reversal (TR) symmetry-broken quantum spin Ha...

[Phys. Rev. B 105, 125126] Published Mon Mar 21, 2022

Author(s): Gaopei Pan, Xu Zhang, Heqiu Li, Kai Sun, and Zi Yang Meng

Employing the recently developed momentum-space quantum Monte Carlo scheme, we study the dynamic response of single-particle and collective excitations in realistic continuum models of twisted bilayer graphene. At charge neutrality with small flat-band dispersion, this unbiased numerical method reve...

[Phys. Rev. B 105, L121110] Published Wed Mar 16, 2022

Author(s): Ioannis Paradisanos, Andres Manuel Saiz Raven, Thierry Amand, Cedric Robert, Pierre Renucci, Kenji Watanabe, Takashi Taniguchi, Iann C. Gerber, Xavier Marie, and Bernhard Urbaszek

The twist angle in transition metal dichalcogenide heterobilayers is a compelling degree of freedom that determines electron correlations and the period of lateral confinement of moiré excitons. Here we perform polarization-resolved second harmonic generation (SHG) spectroscopy of MoS2/WSe2 heterost...

[Phys. Rev. B 105, 115420] Published Fri Mar 18, 2022

Author(s): Shailja Sharma, Shiv Kumar, Girish C. Tewari, Girish Sharma, Eike F. Schwier, Kenya Shimada, A. Taraphder, and C. S. Yadav

We have performed magnetotransport and high-resolution angle-resolved photoelectron spectroscopy (ARPES) measurements on topological insulator PdxBi2Te3(0≤x≤0.20) single crystals. We have observed unusually high values of magnetoresistance (∼1500%) and mobility (∼93000cm2V–1s–1) at low temperatures ...

[Phys. Rev. B 105, 115120] Published Tue Mar 15, 2022

Author(s): M. J. Ambrosio, E. Plésiat, P. Decleva, P. M. Echenique, R. Díez Muiño, and F. Martín

Methods of attosecond science originally developed to investigate systems in the gas phase are currently being adapted to obtain temporal information on the electron dynamics that takes place in condensed-matter systems. In particular, streaking measurements have recently been performed to determine...

[Phys. Rev. B 105, 125405] Published Tue Mar 08, 2022

Author(s): Tao Lei, Jin-Mei Li, Shuai Lu, Li Wang, Qiang Yu, Fang-Sen Li, Jia-Ou Wang, Hui-Qiong Wang, Kurash Ibrahim, and Kai Zhang

The search for novel two-dimensional (2D) giant Rashba semiconductors is a crucial step in the development of spintronic technology. The electronic properties and growth mode of antimonene grown by molecular beam epitaxy were investigated using angle-resolved photoemission spectroscopy (ARPES) and s...

[Phys. Rev. B 105, 115404] Published Fri Mar 04, 2022

Author(s): Yuxuan Wan, Lihai Wang, Kenta Kuroda, Peng Zhang, Keisuke Koshiishi, Masahiro Suzuki, Jaewook Kim, Ryo Noguchi, Cédric Bareille, Koichiro Yaji, Ayumi Harasawa, Shik Shin, Sang-Wook Cheong, Atsushi Fujimori, and Takeshi Kondo

The electronic state of WTe2, a candidate of type-II Weyl semimetal, is investigated by using laser-based spin- and angle-resolved photoemission spectroscopy. We prepare the pair of WTe2 samples, one with a (001) surface and the other with a (001¯) surface, by the “sandwich” method”, and we measure ...

[Phys. Rev. B 105, 085421] Published Wed Feb 23, 2022

Author(s): Jonas Zipfel, Koloman Wagner, Marina A. Semina, Jonas D. Ziegler, Takashi Taniguchi, Kenji Watanabe, Mikhail M. Glazov, and Alexey Chernikov

Radiative recombination of bound-exciton carrier complexes in semiconductors often occurs under simultaneous excitation of either electrons or holes to unbound states. This phenomenon, known as the electron recoil effect, manifests itself in pronounced asymmetric spectral lineshapes of the resulting emission. Monitoring the dynamics of the electron recoil effect in monolayer semiconductors offers access to transient nonequilibrium distributions of the exciton-carrier complexes and their cooling dynamics.

[Phys. Rev. B 105, 075311] Published Thu Feb 24, 2022

Author(s): Fahad Mahmood, Thomas Devereaux, Peter Abbamonte, and Dirk K. Morr

We show theoretically that double photoemission (2e-ARPES) may be used to identify the pairing state in superconductors in which the Cooper pairs have a nonzero center-of-mass momentum, qcm. We theoretically evaluate the 2e-ARPES counting rate P(2) for the cases of a dx2−y2-wave superconductor, a pa...

[Phys. Rev. B 105, 064515] Published Fri Feb 25, 2022

Author(s): Thais Chagas, Omar A. Ashour, Guilherme A. S. Ribeiro, Wendell S. Silva, Zhenglu Li, Steven G. Louie, Rogério Magalhães-Paniago, and Yves Petroff

The electronic topology of Bi4Te3, composed of alternating Bi2 and Bi2Te3 layers, is investigated by density functional theory and angle-resolved photoemission spectroscopy. We find, remarkably, that there are three adjacent strong topological gaps with associated protected surface states within a 2...

[Phys. Rev. B 105, L081409] Published Thu Feb 17, 2022

Author(s): M. Puppin, C. W. Nicholson, C. Monney, Y. Deng, R. P. Xian, J. Feldl, S. Dong, A. Dominguez, H. Hübener, A. Rubio, M. Wolf, L. Rettig, and R. Ernstorfer

Angle-resolved photoelectron spectroscopy is an extremely powerful probe of materials to access the occupied electronic structure with energy and momentum resolution. However, it remains blind to those dynamic states above the Fermi level that determine technologically relevant transport properties....

[Phys. Rev. B 105, 075417] Published Thu Feb 17, 2022

Author(s): Zhe Ying, Shuai Zhang, Bo Chen, Bin Jia, Fucong Fei, Minhao Zhang, Haijun Zhang, Xuefeng Wang, and Fengqi Song

We study the dissipationless transport properties of chiral edge state (CES) in the Chern insulator MnBi2Te4 devices. A near-zero longitudinal resistance and a quantized Hall plateau ∼0.97h/e2 up to 22 K are observed. The CES shows three regimes of temperature dependence, i.e., well-preserved dissip...

[Phys. Rev. B 105, 085412] Published Mon Feb 14, 2022

Author(s): Utso Bhattacharya, Swati Chaudhary, Tobias Grass, Allan S. Johnson, Simon Wall, and Maciej Lewenstein

The breaking of time-reversal symmetry is a crucial ingredient to topological bands. It can occur intrinsically in materials with magnetic order, or be induced by external fields, such as magnetic fields in quantum Hall systems or circularly polarized light fields in Floquet Chern insulators. Apart ...

[Phys. Rev. B 105, L081406] Published Wed Feb 09, 2022

Author(s): T. C. Hu, Q. Wu, Z. X. Wang, L. Y. Shi, Q. M. Liu, L. Yue, S. J. Zhang, R. S. Li, X. Y. Zhou, S. X. Xu, D. Wu, T. Dong, and N. L. Wang

1T′−TaTe2 exhibits an intriguing first-order structural phase transition at around 170 K. Understanding the electronic structural properties is a crucial way to comprehend the origin of this structural phase transition. We performed a combined optical and ultrafast pump-probe study on the compound a...

[Phys. Rev. B 105, 075113] Published Mon Feb 07, 2022

Author(s): Yanchong Zhao, Luojun Du, Shiqi Yang, Jinpeng Tian, Xiaomei Li, Cheng Shen, Jian Tang, Yanbang Chu, Kenji Watanabe, Takashi Taniguchi, Rong Yang, Dongxia Shi, Zhipei Sun, Yu Ye, Wei Yang, and Guangyu Zhang

Atomically thin transition metal dichalcogenides can show a rich variety of bound exciton complex states, such as trions, biexcitons, Fermi polarons, and phonon replicas, because of the reduced dielectric screening and enhanced Coulomb interaction. To date, studies have mainly focused on the complex...

[Phys. Rev. B 105, L041411] Published Mon Jan 31, 2022

Author(s): Felix Lüpke, Anh D. Pham, Yi-Fan Zhao, Ling-Jie Zhou, Wenchang Lu, Emil Briggs, Jerzy Bernholc, Marek Kolmer, Jacob Teeter, Wonhee Ko, Cui-Zu Chang, Panchapakesan Ganesh, and An-Ping Li

The interplay of nontrivial band topology and magnetism gives rise to a series of exotic quantum phenomena, such as the emergent quantum anomalous Hall (QAH) effect and topological magnetoelectric effect. Many of these quantum phenomena have local manifestations when the global symmetry is broken. H...

[Phys. Rev. B 105, 035423] Published Thu Jan 20, 2022

Author(s): Wei Wang, Chen Si, Wen Lei, Feng Xiao, Yunhui Liu, Carmine Autieri, and Xing Ming

Two-dimensional (2D) layered materials have attracted tremendous interest from the perspective of basic physics and technological applications in the last decade. Especially, the artificially assembled van der Waals (vdW) heterostructures and twisted 2D materials bring out fascinating properties, an...

[Phys. Rev. B 105, 035119] Published Tue Jan 11, 2022

Author(s): Daniel Erkensten, Samuel Brem, Koloman Wagner, Roland Gillen, Raül Perea-Causín, Jonas D. Ziegler, Takashi Taniguchi, Kenji Watanabe, Janina Maultzsch, Alexey Chernikov, and Ermin Malic

Excitons govern the optical properties of semiconducting transition metal dichalcogenides. At elevated electron-hole densities excitons are subject to efficient exciton-exciton annihilation (EEA), an Auger recombination process that fundamentally limits the performance of optoelectronic devices. Here, the authors combine microscopic modeling with time-resolved photoluminescence measurements to demonstrate the crucial role of dark intervalley excitons for an efficient EEA in WSe2 monolayers. In particular, they find both in theory and experiment a drastic increase in the EEA at intermediate temperatures.

[Phys. Rev. B 104, L241406] Published Fri Dec 17, 2021

Author(s): Y. Falke, N. Ehlen, G. Marini, A. V. Fedorov, V. Y. Voroshnin, B. V. Senkovskiy, K. Nikonov, M. Hoesch, T. K. Kim, L. Petaccia, G. Di Santo, T. Szkopek, G. Profeta, and A. Grüneis

We investigate electron-phonon coupling (EPC) in the charge density wave (CDW) phase of VSe2 by Raman spectroscopy, angle-resolved photoemission spectroscopy (ARPES), and ab initio calculations. Zone folding induced by the 4×4 in-plane CDW phase promotes the appearance of a Raman peak at ∼170cm−1. T...

[Phys. Rev. B 104, 235137] Published Mon Dec 20, 2021

Author(s): T. Yilmaz and E. Vescovo

Here, we study the surface electronic structure of 1T−VSe2 by means of angle-resolved photoemission spectroscopy and uncover a dispersionless emission located in the vicinity of the Fermi level. Its crystal momentum dependency reveals that it occupies large portions of the Brillouin zone, where no b...

[Phys. Rev. B 105, L041101] Published Mon Jan 03, 2022

Author(s): Nicola Lanatà

We propose an operatorially exact formalism for describing the equilibrium and quantum-dynamical properties of many-electron systems interacting locally on a lattice, called “ghost rotationally invariant slave-boson theory” (g-RISB). We demonstrate that our theoretical framework reduces to the recen...

[Phys. Rev. B 105, 045111] Published Wed Jan 05, 2022

Author(s): Zongxiu Wu, Kunliang Bu, Wenhao Zhang, Ying Fei, Yuan Zheng, Jingjing Gao, Xuan Luo, Zheng Liu, Yu-Ping Sun, and Yi Yin

New theoretical proposals and experimental findings on transition metal dichalcogenide 1T−TaS2 have revived interest in its possible Mott insulating state. We perform a comprehensive scanning tunneling microscopy and spectroscopy experiment on different single-step areas in pristine 1T−TaS2. After a...

[Phys. Rev. B 105, 035109] Published Thu Jan 06, 2022

Author(s): Wenhao Zhang, Zongxiu Wu, Kunliang Bu, Ying Fei, Yuan Zheng, Jingjing Gao, Xuan Luo, Zheng Liu, Yu-Ping Sun, and Yi Yin

The origin of different electronic states of 1T−TaS2 and 1T−TaSe2 remains controversial due to the complicated correlated electronic properties. We apply scanning tunneling microscopy to study the electronic state of bulk 1T−TaSe2. Both insulating and metallic states are identified in different area...

[Phys. Rev. B 105, 035110] Published Thu Jan 06, 2022

Author(s): Ningning Liu, Yupeng Li, Ping Li, Gang Yao, Yueqiao Qu, Yanfu Wu, Dan-Dan Guan, Shiyong Wang, Hao Zheng, Yao-Yi Li, Zhu-An Xu, Weidong Luo, Canhua Liu, and Jin-Feng Jia

Disorder caused by defects plays an important role on the emergence of exotic physical phenomena in quantum states of materials, including charge density waves (CDWs). Usually, the coexistence of multiphase CDWs aroused by defects is manifested in multiple domains resulting from phase separation. By...

[Phys. Rev. B 104, 235410] Published Thu Dec 09, 2021

Author(s): Qi Jiang, Deyang Wang, Zhengtai Liu, Zhicheng Jiang, Haoji Qian, Xiaoping Shen, Ang Li, Dawei Shen, Shan Qiao, and Mao Ye

Topological superconductors are materials in which superconductivity is closely entangled with topological electronic states. This provides a promising route to create Majorana bound states that are of fundamental importance to fault-tolerant quantum computation. In this paper, the recently discover...

[Phys. Rev. B 104, 245112] Published Tue Dec 07, 2021

Author(s): M. Weis, K. Balin, B. Wilk, T. Sobol, A. Ciavardini, G. Vaudel, V. Juvé, B. Arnaud, B. Ressel, M. Stupar, K. C. Prince, G. De Ninno, P. Ruello, and J. Szade

Topological insulators (TIs) are promising materials for future spintronic applications such as emerging spin-to-charge conversion (SCC) devices, possibly working at GHz-THz frequency for ultrafast data processing. These devices will rely on hybrid nanostructures composed, for example, of a ferromag...

[Phys. Rev. B 104, 245110] Published Mon Dec 06, 2021