Results 111 to 120 of about 53,071 (272)

Topological Switch between Second-Order Topological Insulators and Topological Crystalline Insulators

Physical Review Letters, 2018
We investigate a topological switch between second-order topological insulators (SOTIs) and topological crystalline insulators (TCIs). Both the SOTI and the TCI are protected by the mirror and inversion symmetries, for which we define the bulk topological numbers of the same type. We take examples of square nanodisks on the square lattice and hexagonal
openaire   +4 more sources

Kelvin Probe Force Microscopy in Bionanotechnology: Current Advances and Future Perspectives

Advanced Materials, EarlyView.
Kelvin probe force microscopy (KPFM) enables the nanoscale mapping of electrostatic surface potentials. While widely applied in materials science, its use in biological systems remains emerging. This review presents recent advances in KPFM applied to biological samples and provides a critical perspective on current limitations and future directions for
Ehsan Rahimi, Mario Palacios‐Corella, Arjan Mol, Salvador Pané, Josep Puigmartí‐Luis   +4 more
wiley   +1 more source

Microscopic Insights into Magnetic Warping and Time‐Reversal Symmetry Breaking in Topological Surface States of Rare‐Earth‐Doped Bi2Te3

Advanced Materials, EarlyView.
Magnetic doping of the topological insulator Bi2Te3 with erbium adatoms induces out‐of‐plane magnetism and breaks time‐reversal symmetry, opening a Dirac gap and driving a Fermi surface transition from hexagonal to star‐of‐David geometry. Microscopy, spectroscopy, and magnetic dichroism reveal atomically controlled magnetic interactions that tailor the
Beatriz Muñiz Cano, Fabián Calleja, Ji Dai, Massimo Tallarida, Vera Marinova, Alessandro Barla, Marc G. Cuxart, Pierluigi Gargiani, Gonzalo N. Molina, José Angel Silva‐Guillén, Adriana I. Figueroa, Kevin García‐Díez, Sergio O. Valenzuela, Aitor Mugarza, Amadeo L. Vázquez de Parga, Rodolfo Miranda, Francisco Guinea, Manuela Garnica, Miguel A. Valbuena   +18 more
wiley   +1 more source

A toy model for quantum spin Hall effect

, 2015
In this Communication, we investigate a toy model of three-dimensional topological insulator surface, coupled homogeneously to a fictitious pseudo spin-$\frac{1}{2}$ particle.
Nsofini, J., Owerre, S. A.
core   +1 more source

Opportunities of Semiconducting Oxide Nanostructures as Advanced Luminescent Materials in Photonics

Advanced Materials, EarlyView.
The review discusses the challenges of wide and ultrawide bandgap semiconducting oxides as a suitable material platform for photonics. They offer great versatility in terms of tuning microstructure, native defects, doping, anisotropy, and micro‐ and nano‐structuring. The review focuses on their light emission, light‐confinement in optical cavities, and
Ana Cremades, Pedro Hidalgo, David Maestre, Ruth Martínez‐Casado, Emilio Nogales, Beatriz Rodríguez, G. Cristian Vásquez, Bianchi Méndez   +7 more
wiley   +1 more source

Topological invariants, surface states, and interaction-driven phase transitions in correlated Kondo insulators with cubic symmetry

, 2014
We construct a lattice model for a cubic Kondo insulator consisting of one spin-degenerate $d$ and $f$ orbital at each lattice site. The odd-parity hybridization between the two orbitals permits us to obtain various trivial and topological insulating ...
Legner, Markus, Rüegg, Andreas, Sigrist, Manfred   +2 more
core   +1 more source

Self‐Assembled Inorganic Nanomembrane Tubes: Rolled‐Up Piezoelectrics for Microacoustic Wave‐Based Actuators and Sensors

Advanced Materials, EarlyView.
This study demonstrates a self‐assembly process to generate free‐standing piezoelectric nanomembranes, forming ultracompact microtubular acoustic wave sensors and actuators. The miniaturized 3D piezoelectric platform reported in this work can be applied in telecommunication, energy harvesting, and acoustofluidics. Moreover, the 3D self‐assembly can add
Raphaël C. L‐M. Doineau, Christian N. Saggau, Stefan Baunack, Thomas Gemming, Yara Abdelaal, Robert Weser, Oliver G. Schmidt, Hagen Schmidt, Andreas Winkler, Mariana Medina‐Sánchez   +9 more
wiley   +1 more source

Experimental Observation of Temperature-Driven Topological Phase Transition in HgTe/CdHgTe Quantum Wells

Condensed Matter, 2019
We report on the comparison between temperature-dependent magneto-absorption and magnetotransport spectroscopy of HgTe/CdHgTe quantum wells in terms of the detection of the phase transition between the topological insulator and band insulator states. Our
Maksim S. Zholudev, Aleksandr M. Kadykov, Mikhail A. Fadeev, Michal Marcinkiewicz, Sandra Ruffenach, Christophe Consejo, Wojciech Knap, Jeremie Torres, Sergey V. Morozov, Vladimir I. Gavrilenko, Nikolay N. Mikhailov, Sergey A. Dvoretskii, Frederic Teppe   +12 more
doaj   +1 more source

Flexoelectrically Induced Polar Topology in Twisted SrTiO3 Membranes

Advanced Materials, EarlyView.
Twisted SrTiO3 bilayers host polar vortices of flexoelectric origin, revealed through combined experiment and theory. By reconstructing polarization from the toroidal moment of strain gradients, the work establishes a 3D chiral state with broken inversion and mirror symmetries.
Isabel Tenreiro, Hugo Aramberri, Víctor Rouco, Gabriel Sánchez‐Santolino, Mariona Cabero, Fernando Gallego, David Sánchez‐Manzano, José M. González‐Calbet, Federico Mompeán, Mar García‐Hernández, Alberto Rivera‐Calzada, Jorge Íñiguez‐González, Carlos León, Jacobo Santamaría   +13 more
wiley   +1 more source

Bulk-boundary correspondence in three dimensional topological insulators

, 2011
We discuss the relation between bulk topological invariants and the spectrum of surface states in three dimensional non-interacting topological insulators.
A. I. Akhiezer, D. J. Thouless, G. L. Bir, G. Ortiz, L. Isaev, L. P. Pitaevskii, M. V. Kisin, S. Yu. Potapenko, V. A. Volkov, V. G. Bagrov, Y. H. Moon   +10 more
core   +1 more source