Results 71 to 80 of about 18,734 (309)

Recent Advances in Wide‐Bandgap Perovskite Solar Cells

Advanced Materials, EarlyView.
Ubiquitous defects predominately account for photo‐instability and open‐circuit voltage losses in wide‐bandgap perovskite solar cells (WBG PSCs). This review comprehensively presents the underlying impact mechanisms, summarizes the advanced optimization strategies across various functional layers and their interfaces to develop efficient and stable WBG
Jianjun Mei, Feng Yan
wiley   +1 more source

Half-quantum mirror Hall effect

Nature Communications
We predict a half-quantized mirror Hall effect induced by mirror symmetry in strong topological insulator films. These films are known to host a pair of gapless Dirac cones in the first Brillouin zone associated with surface electrons.
Bo Fu, Kai-Zhi Bai, Shun-Qing Shen
doaj   +1 more source

Spontaneous In‐Plane Anomalous Hall Response Observed in a Ferromagnetic Oxide

Advanced Materials, EarlyView.
Observation of in‐plane anomalous Hall effect (AHE) is demonstrated in a typical ferromagnet SrRuO3. The (111)‐orientated ultrathin films with in‐plane easy axes exhibit spontaneous AHE at zero field, which is controllable via its intrinsic coupling to the in‐plane spin magnetization through higher order effects allowed by symmetry, revealing the ...
Shinichi Nishihaya, Yuta Matsuki, Haruto Kaminakamura, Hiroki Sugeno, Ming‐Chun Jiang, Yoshiya Murakami, Ryotaro Arita, Hiroaki Ishizuka, Masaki Uchida   +8 more
wiley   +1 more source

Spatiotemporally Resolved Orbital Hall Effect in a Topological Semimetal

Advanced Materials, EarlyView.
Real‐space mapping of orbital angular momentum (OAM) transport is achieved using contact‐free polarimetric terahertz spectroscopy. This principle is applied to the topological semimetal Td‐WTe2, revealing the spatial separation of electrons into two distinct regions characterized by opposite out‐of‐plane OAM (±Lz).
Byung Cheol Park, Taewoo Ha, Hojun Lee, Kyung Ik Sim, Insu Baek, Seok Joon Yun, Kyujoon Lee, Hyun‐Woo Lee, Young Hee Lee   +8 more
wiley   +1 more source

Terahertz Electronic and Spin Currents in Wafer‐Scale Van der Waals Bi2Se3/WSe2 Heterostructures and Polymorphs

Advanced Materials, EarlyView.
Van der Waals heterostructures offer exciting possibilities for artificial materials with unique optical, electronic, and spintronic properties. However, their use in the terahertz (THz) range is limited due to material constraints. This study demonstrates scalable, large‐area, crystalline 2D heterostructures, combining topological insulators ...
M. Mičica, A. Wright, S. Massabeau, S. Ayari, E. Rongione, M. Oliveira Ribeiro, S. Husain, R. Sharma, T. Denneulin, R. E. Dunin‐Borkowski, J. Mangeney, J. Tignon, R. Lebrun, H. Okuno, O. Boulle, A. Marty, F. Bonell, F. Carosella, H. Jaffrés, R. Ferreira, J.‐M. George, M. Jamet, S. Dhillon   +22 more
wiley   +1 more source

A model study of present-day Hall-effect circulators

EPJ Quantum Technology, 2017
Stimulated by the recent implementation of a three-port Hall-effect microwave circulator of Mahoney et al. (MEA), we present model studies of the performance of this device.
B Placke, S Bosco, DP DiVincenzo
doaj   +1 more source

The quantum Hall effect on

Comptes Rendus Physique, 2003
Zhang and Hu have formulated an SU(2) quantum Hall system on the four-sphere, with interesting three-dimensional boundary dynamics including gapless states of nonzero helicity. In order to understand the local physics of their model we study the U(1) and SU(2) quantum Hall systems on flat R^4, with flat boundary R^3.
Joseph Polchinski, Henriette Elvang
openaire   +3 more sources

AC Current‐Driven Magnetization Switching and Nonlinear Hall Rectification in a Magnetic Topological Insulator

Advanced Materials, EarlyView.
This study reports alternating‐current (AC) driven magnetization reversal in a semi‐magnetic topological insulator (Cr,Bi,Sb)2Te3/(Bi,Sb)2Te3, with low current density. Time‐domain Hall voltage measurements reveal a nonlinear and rectified Hall effect, along with higher‐harmonic responses and hysteresis.
Yuto Kiyonaga, Masataka Mogi, Ryutaro Yoshimi, Yukako Fujishiro, Yuri Suzuki, Max T. Birch, Atsushi Tsukazaki, Minoru Kawamura, Masashi Kawasaki, Yoshinori Tokura   +9 more
wiley   +1 more source

Photonic Anomalous Quantum Hall Effect

Physical Review Letters, 2019
We experimentally realize a photonic analogue of the anomalous quantum Hall insulator using a two-dimensional (2D) array of coupled ring resonators. Similar to the Haldane model, our 2D array is translation invariant, has zero net gauge flux threading the lattice, and exploits next-nearest neighbor couplings to achieve a topologically non-trivial ...
Mittal, Sunil, Orre, Venkata Vikram, Leykam, Daniel, Chong, Yi Dong, Mohammad Hafezi   +4 more
openaire   +6 more sources

Emergent Berry Curvature in Inversion‐Symmetric Photonic Crystals for Ultraconfined Topological States

Advanced Materials, EarlyView.
In this work, nonzero Berry curvature in photonic crystals is induced by breaking unit cell inversion symmetry through spatial shifts rather than geometrical modifications. This enables the design of ultraconfined topological states with subwavelength in‐plane field confinement and out‐of‐plane field isolation.
Yi Ji Tan, Ranjan Singh
wiley   +1 more source