skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Emergence of topological electronic phases in elemental lithium under pressure

Abstract

Lithium, a prototypical simple metal under ambient conditions, has a surprisingly rich phase diagram under pressure, taking up several structures with reduced symmetry, low coordination numbers, and even semiconducting character with increasing density. Using first-principles calculations, we demonstrate that some predicted high-pressure phases of elemental Li also host topological electronic structures. Beginning at 80 GPa and coincident with a transition to the previously predicted Pbca phase, we find Li to be a Dirac nodal line semimetal. We further calculate that Li retains linearly dispersing energy bands near the Fermi energy in subsequent predicted higher-pressure phases and that it exhibits a Lifshitz transition between two Cmca phases at 220 GPa. The Fd 3 ¯ m phase at 500 GPa forms buckled honeycomb layers that give rise to a Dirac crossing 1 eV below the Fermi energy. The well-isolated topological nodes near the Fermi level in these phases result from increasing p-orbital character with density at the Fermi level, itself a consequence of rising 1s core wavefunction overlap, and a preference for nonsymmorphic symmetries in the crystal structures favored at these pressures. Our results provide evidence that under pressure, bulk 3D materials with light elements, or even pure elemental systems, can undergo phase transitions hosting nontrivial topological phase transitions hosting nontrivial topological properties near the Fermi level with measurable consequences and that, through pressure, we can access these phases in elemental lithium.

Authors:
; ;
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
1508691
Grant/Contract Number:  
AC02-05CH11231
Resource Type:
Journal Article: Published Article
Journal Name:
Proceedings of the National Academy of Sciences of the United States of America
Additional Journal Information:
Journal Name: Proceedings of the National Academy of Sciences of the United States of America; Journal ID: ISSN 0027-8424
Publisher:
Proceedings of the National Academy of Sciences
Country of Publication:
United States
Language:
English

Citation Formats

Mack, Stephanie A., Griffin, Sinéad M., and Neaton, Jeffrey B. Emergence of topological electronic phases in elemental lithium under pressure. United States: N. p., 2019. Web. doi:10.1073/pnas.1821533116.
Mack, Stephanie A., Griffin, Sinéad M., & Neaton, Jeffrey B. Emergence of topological electronic phases in elemental lithium under pressure. United States. doi:10.1073/pnas.1821533116.
Mack, Stephanie A., Griffin, Sinéad M., and Neaton, Jeffrey B. Wed . "Emergence of topological electronic phases in elemental lithium under pressure". United States. doi:10.1073/pnas.1821533116.
@article{osti_1508691,
title = {Emergence of topological electronic phases in elemental lithium under pressure},
author = {Mack, Stephanie A. and Griffin, Sinéad M. and Neaton, Jeffrey B.},
abstractNote = {Lithium, a prototypical simple metal under ambient conditions, has a surprisingly rich phase diagram under pressure, taking up several structures with reduced symmetry, low coordination numbers, and even semiconducting character with increasing density. Using first-principles calculations, we demonstrate that some predicted high-pressure phases of elemental Li also host topological electronic structures. Beginning at 80 GPa and coincident with a transition to the previously predicted Pbca phase, we find Li to be a Dirac nodal line semimetal. We further calculate that Li retains linearly dispersing energy bands near the Fermi energy in subsequent predicted higher-pressure phases and that it exhibits a Lifshitz transition between two Cmca phases at 220 GPa. The Fd 3 ¯ m phase at 500 GPa forms buckled honeycomb layers that give rise to a Dirac crossing 1 eV below the Fermi energy. The well-isolated topological nodes near the Fermi level in these phases result from increasing p-orbital character with density at the Fermi level, itself a consequence of rising 1s core wavefunction overlap, and a preference for nonsymmorphic symmetries in the crystal structures favored at these pressures. Our results provide evidence that under pressure, bulk 3D materials with light elements, or even pure elemental systems, can undergo phase transitions hosting nontrivial topological phase transitions hosting nontrivial topological properties near the Fermi level with measurable consequences and that, through pressure, we can access these phases in elemental lithium.},
doi = {10.1073/pnas.1821533116},
journal = {Proceedings of the National Academy of Sciences of the United States of America},
issn = {0027-8424},
number = ,
volume = ,
place = {United States},
year = {2019},
month = {4}
}

Journal Article:
Free Publicly Available Full Text
This content will become publicly available on October 24, 2019
Publisher's Version of Record

Save / Share:

Works referenced in this record:

From ultrasoft pseudopotentials to the projector augmented-wave method
journal, January 1999


Ab initiomolecular dynamics for liquid metals
journal, January 1993


The electronic properties of graphene
journal, January 2009

  • Castro Neto, A. H.; Guinea, F.; Peres, N. M. R.
  • Reviews of Modern Physics, Vol. 81, Issue 1, p. 109-162
  • DOI: 10.1103/RevModPhys.81.109

Colloquium: Topological insulators
journal, November 2010


Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set
journal, October 1996