skip to main content

DOE PAGESDOE PAGES

Title: Predicted Realization of Cubic Dirac Fermion in Quasi-One-Dimensional Transition-Metal Monochalcogenides

We show that the previously predicted “cubic Dirac fermion,” composed of six conventional Weyl fermions including three with left-handed and three with right-handed chirality, is realized in a specific, stable solid state system that has been made years ago, but was not appreciated as a “cubically dispersed Dirac semimetal” (CDSM). We identify the crystal symmetry constraints and find the space group P6 3/m as one of the two that can support a CDSM, of which the characteristic band crossing has linear dispersion along the principle axis but cubic dispersion in the plane perpendicular to it. We then conduct a material search using density functional theory, identifying a group of quasi-one-dimensional molybdenum monochalcogenide compounds A I(MoX VI) 3 (AI = Na, K, Rb, In, Tl; X VI = S , Se, Te) as ideal CDSM candidates. Studying the stability of the A ( MoX ) 3 family reveals a few candidates such as Rb(MoTe) 3 and Tl(MoTe) 3 that are predicted to be resilient to Peierls distortion, thus retaining the metallic character. Furthermore, the combination of one dimensionality and metallic nature in this family provides a platform for unusual optical signature—polarization-dependent metallic vs insulating response.
Authors:
 [1] ;  [1]
  1. Univ. of Colorado, Boulder, CO (United States). Renewable and Sustainable Energy Institute
Publication Date:
Grant/Contract Number:
SC0010467; AC02-05CH11231
Type:
Published Article
Journal Name:
Physical Review. X
Additional Journal Information:
Journal Volume: 7; Journal Issue: 2; Journal ID: ISSN 2160-3308
Publisher:
American Physical Society
Research Org:
Univ. of Colorado, Boulder, CO (United States)
Sponsoring Org:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22). Materials Sciences & Engineering Division; USDOE
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; Condense Matter Physics; Materials Science
OSTI Identifier:
1356278
Alternate Identifier(s):
OSTI ID: 1424916