Direct observation of nodes and twofold symmetry in FeSe superconductor.

Science

State Key Laboratory for Low-Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, the People's Republic of China.

Published: June 2011

We investigated the electron-pairing mechanism in an iron-based superconductor, iron selenide (FeSe), using scanning tunneling microscopy and spectroscopy. Tunneling conductance spectra of stoichiometric FeSe crystalline films in their superconducting state revealed evidence for a gap function with nodal lines. Electron pairing with twofold symmetry was demonstrated by direct imaging of quasiparticle excitations in the vicinity of magnetic vortex cores, Fe adatoms, and Se vacancies. The twofold pairing symmetry was further supported by the observation of striped electronic nanostructures in the slightly Se-doped samples. The anisotropy can be explained in terms of the orbital-dependent reconstruction of electronic structure in FeSe.

Download full-text PDF

Source
http://dx.doi.org/10.1126/science.1202226DOI Listing

Publication Analysis

Top Keywords

twofold symmetry
8
direct observation
4
observation nodes
4
nodes twofold
4
fese
4
symmetry fese
4
fese superconductor
4
superconductor investigated
4
investigated electron-pairing
4
electron-pairing mechanism
4

Similar Publications

Synthesis and structure of -2,5-di-methyl-piperazine-1,4-diium di-hydrogen diphosphate.

Acta Crystallogr E Crystallogr Commun

October 2024

Laboratory of Materials Chemistry (LR13ES08), Faculty of Sciences of Bizerte, University of Carthage, 7021 Zarzouna, Bizerte, Tunisia.

In the title salt, CHN ·HPO , the complete dication is generated by a crystallographic centre of symmetry with the methyl groups in equatorial orientations. The complete dianion is generated by a crystallographic twofold axis with the central O atom lying on the axis: the P-O-P bond angle is 135.50 (12)°.

View Article and Find Full Text PDF

Structural insights into Semiliki forest virus receptor binding modes indicate novel mechanism of virus endocytosis.

PLoS Pathog

December 2024

State Key Laboratory for Animal Disease Control and Prevention & National Data Center for Animal Infectious Diseases, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, People's Republic of China.

The Very Low-Density Lipoprotein Receptor (VLDLR) is an entry receptor for the prototypic alphavirus Semliki Forest Virus (SFV). However, the precise mechanisms underlying the entry of SFV into cells mediated by VLDLR remain unclear. In this study, we found that of the eight class A (LA) repeats of the VLDLR, only LA2, LA3, and LA5 specifically bind to the native SFV virion while synergistically promoting SFV cell attachment and entry.

View Article and Find Full Text PDF

Twofold Anisotropic Superconductivity in Bilayer T_{d}-MoTe_{2}.

Phys Rev Lett

November 2024

Department of Materials Science and Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA.

Article Synopsis
  • Noncentrosymmetric two-dimensional superconductors like few-layer T_{d}-MoTe_{2} exhibit unique superconducting properties, including upper critical fields exceeding the Pauli limit by up to 600%.
  • The enhancement of these properties is still debated, with theories suggesting influences from either spin-orbit parity coupling or tilted Ising spin-orbit coupling.
  • In bilayer T_{d}-MoTe_{2}, experiments show superconductivity has a twofold symmetry influenced by magnetic and electric fields, and findings support tilted Ising spin-orbit coupling as the main mechanism.
View Article and Find Full Text PDF

Spontaneous symmetry breaking and more recently entanglement are two cornerstones of quantum matter. We introduce the notion of anisotropic entanglement ordered phases, where the spatial profile of spin-pseudospin entanglement spontaneously lowers the fourfold rotational symmetry of the underlying crystal to a twofold one, while the charge density retains the full symmetry. The resulting phases, which we term entanglement smectic and entanglement stripe, exhibit a rich Goldstone mode spectrum and a set of phase transitions as a function of underlying anisotropies.

View Article and Find Full Text PDF

Twisted Magnetic Van der Waals Bilayers: An Ideal Platform for Altermagnetism.

Phys Rev Lett

November 2024

Centre for Quantum Physics, Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement (MOE), School of Physics, Beijing Institute of Technology, Beijing 100081, China.

We introduce a universal methodology for generating and manipulating altermagnetism in two-dimensional (2D) magnetic Van der Waals (MvdW) materials through twisting. We find that a key in-plane twofold rotational operation can be achieved in a twisted bilayer of any 2D MvdW material, which takes one of all five 2D Bravais lattices, thereby inducing altermagnetism. By choosing the constituent MvdW monolayer with specific symmetry, our approach can tailor altermagnetism of any type, such as d wave, g wave, and i wave.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!