DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Observation of Double Weyl Phonons in Parity-Breaking FeSi

Journal Article · · Physical Review Letters
 [1];  [2];  [2];  [1];  [3];  [1];  [4];  [5];  [5];  [1]
  1. Brookhaven National Lab. (BNL), Upton, NY (United States). Condensed Matter Physics and Materials Science Dept.
  2. Chinese Academy of Sciences (CAS), Beijing (China). Beijing National Lab. for Condensed Matter Physics. Inst. of Physics; Univ. of Chinese Academy of Sciences, Beijing (China)
  3. Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source
  4. Chinese Academy of Sciences (CAS), Beijing (China). Beijing National Lab. for Condensed Matter Physics. Inst. of Physics
  5. Chinese Academy of Sciences (CAS), Beijing (China). Beijing National Lab. for Condensed Matter Physics. Inst. of Physics; Collaborative Innovation Center of Quantum Matter, Beijing (China)

Condensed matter systems have now become a fertile ground to discover emerging topological quasiparticles with symmetry protected modes. While many studies have focused on fermionic excitations, the same conceptual framework can also be applied to bosons yielding new types of topological states. Motivated by Zhang et al.’s recent theoretical prediction of double Weyl phonons in transition metal monosilicides [Phys. Rev. Lett. 120, 016401 (2018)], in this paper we directly measure the phonon dispersion in parity-breaking FeSi using inelastic x-ray scattering. Finally, by comparing the experimental data with theoretical calculations, we make the first observation of double Weyl points in FeSi, which will be an ideal material to explore emerging bosonic excitations and its topologically nontrivial properties.

Research Organization:
Brookhaven National Laboratory (BNL), Upton, NY (United States); Argonne National Laboratory (ANL), Argonne, IL (United States); Chinese Academy of Sciences (CAS), Beijing (China)
Sponsoring Organization:
USDOE Office of Science (SC), Basic Energy Sciences (BES); National Key Research and Development Program of China; National Natural Science Foundation of China (NSFC); Chinese Academy of Sciences; Chinese Academy of Sciences (CAS)
Grant/Contract Number:
SC0012704; AC02-06CH11357; 2016YFA0300600; 11674369; 11774399; XDB07020100; QYZDB-SSW-SLH043; 1047478
OSTI ID:
1460696
Alternate ID(s):
OSTI ID: 1460886; OSTI ID: 1467437
Report Number(s):
BNL-207825-2018-JAAM; TRN: US1901900
Journal Information:
Physical Review Letters, Vol. 121, Issue 3; ISSN 0031-9007
Publisher:
American Physical Society (APS)Copyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 117 works
Citation information provided by
Web of Science

References (42)

Topological mechanics of gyroscopic metamaterials journal November 2015
Quick iterative scheme for the calculation of transfer matrices: application to Mo (100) journal May 1984
Topological insulators and superconductors journal October 2011
Magnetic moments induce strong phonon renormalization in FeSi journal November 2015
Weyl and Dirac semimetals in three-dimensional solids journal January 2018
Phonons and related crystal properties from density-functional perturbation theory journal July 2001
Observation of topological valley transport of sound in sonic crystals journal December 2016
Floquet topological insulators for sound journal June 2016
Observation of phononic helical edge states in a mechanical topological insulator journal July 2015
Colloquium: Topological insulators journal November 2010
Synthetic gauge flux and Weyl points in acoustic systems journal September 2015
Topological Phonon Modes and Their Role in Dynamic Instability of Microtubules journal December 2009
Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set journal October 1996
Topological Phononic Crystals with One-Way Elastic Edge Waves journal September 2015
Incommensurate Phonon Anomaly and the Nature of Charge Density Waves in Cuprates journal January 2018
Double-Weyl Phonons in Transition-Metal Monosilicides journal January 2018
Six-reflection meV-monochromator for synchrotron radiation journal May 2011
New developments in fabrication of high-energy-resolution analyzers for inelastic X-ray spectroscopy journal March 2011
Classification of topological phonons in linear mechanical metamaterials journal August 2016
WannierTools: An open-source software package for novel topological materials journal March 2018
Topological Acoustics journal March 2015
Dynamical matrices, Born effective charges, dielectric permittivity tensors, and interatomic force constants from density-functional perturbation theory journal April 1997
Acoustic topological insulator and robust one-way sound transport journal August 2016
Topological mechanics journal June 2016
Topological boundary modes in isostatic lattices journal December 2013
Phonon line shapes and excitation energies journal June 1997
Nonlinear conduction via solitons in a topological mechanical insulator journal August 2014
Highly convergent schemes for the calculation of bulk and surface Green functions journal April 1985
Topologically protected elastic waves in phononic metamaterials journal November 2015
Dispersion tuning and route reconfiguration of acoustic waves in valley topological phononic crystals journal February 2020
Magnetic moments induce strong phonon renormalization in FeSi text January 2015
Incommensurate Phonon Anomaly and the Nature of Charge Density Waves in Cuprates text January 2018
Topological Phonon Modes and their Role in Dynamic Instability of Microtubules journal January 2013
WannierTools: An open-source software package for novel topological materials text January 2018
Topological phonon modes and their role in dynamic instability of microtubules text January 2009
Topological Boundary Modes in Isostatic Lattices text January 2013
Topological mechanics of gyroscopic metamaterials text January 2015
Floquet Topological Insulators for Sound text January 2015
WannierTools: An open-source software package for novel topological materials text January 2017
Weyl and Dirac Semimetals in Three Dimensional Solids text January 2017
Double-Weyl phonons in transition-metal monosilicides text January 2017
Observation of topological valley transport of sound in sonic crystals text January 2017

Cited By (8)

Topological Phononics: From Fundamental Models to Real Materials journal August 2019
Topological triply degenerate point with double Fermi arcs journal April 2019
Topology of triple-point metals journal July 2019
Phononic Weyl points and one-way topologically protected nontrivial phononic surface arc states in noncentrosymmetric WC-type materials journal May 2019
Experimental Realization of Type-II Weyl Points and Fermi Arcs in Phononic Crystal journal March 2019
Three-Dimensional Topological States of Phonons with Tunable Pseudospin Physics journal July 2019
AlB2 and MgB2: a comparative study of their electronic, phonon and superconductivity properties via first principles text January 2020
AlB 2 and MgB 2 : a comparative study of their electronic, phonon and superconductivity properties via first principles journal April 2020

Figures / Tables (4)