We report measurements and calculations on the properties of the intermetallic compound Be5Pt. High-quality polycrystalline samples show a nearly constant temperature dependence of the electrical resistivity over a wide temperature range. On the other hand, relativistic electronic structure calculations indicate the existence of a narrow pseudogap in the density of states arising from accidental approximate Dirac cones extremely close to the Fermi level. A small true gap of order ∼3 meV is present at the Fermi level, yet the measured resistivity is nearly constant from low to room temperature. We argue that this unexpected behavior can be understood by a cancellation of the energy dependence of density of states and relaxation time due to disorder, and discuss a model for electronic transport. With applied pressure, the resistivity becomes semiconducting, consistent with theoretical calculations that show that the bandgap increases with applied pressure. We further discuss the role of Be inclusions in the samples.

Remarkable low-energy properties of the pseudogapped semimetal Be5Pt / Fanfarillo, Laura; Hamlin, J. J.; Hennig, R. G.; Hire, Ajinkya C.; Hirschfeld, P. J.; Kim, Jungsoo; Lim, Jinhyuk; Quan, Yundi; Stewart, G. R.; Xie, Stephen R.. - In: PHYSICAL REVIEW. B. - ISSN 2469-9950. - 102:15(2020), pp. 1-11. [10.1103/PhysRevB.102.155206]

Remarkable low-energy properties of the pseudogapped semimetal Be5Pt

Fanfarillo, Laura
Membro del Collaboration group
;
2020-01-01

Abstract

We report measurements and calculations on the properties of the intermetallic compound Be5Pt. High-quality polycrystalline samples show a nearly constant temperature dependence of the electrical resistivity over a wide temperature range. On the other hand, relativistic electronic structure calculations indicate the existence of a narrow pseudogap in the density of states arising from accidental approximate Dirac cones extremely close to the Fermi level. A small true gap of order ∼3 meV is present at the Fermi level, yet the measured resistivity is nearly constant from low to room temperature. We argue that this unexpected behavior can be understood by a cancellation of the energy dependence of density of states and relaxation time due to disorder, and discuss a model for electronic transport. With applied pressure, the resistivity becomes semiconducting, consistent with theoretical calculations that show that the bandgap increases with applied pressure. We further discuss the role of Be inclusions in the samples.
2020
102
15
1
11
155206
10.1103/PhysRevB.102.155206
https://journals.aps.org/prb/abstract/10.1103/PhysRevB.102.155206
Fanfarillo, Laura; Hamlin, J. J.; Hennig, R. G.; Hire, Ajinkya C.; Hirschfeld, P. J.; Kim, Jungsoo; Lim, Jinhyuk; Quan, Yundi; Stewart, G. R.; Xie, Stephen R.
File in questo prodotto:
File Dimensione Formato  
PhysRevB.102.155206.pdf

accesso aperto

Descrizione: Versione pubblicata dell'articolo
Tipologia: Versione Editoriale (PDF)
Licenza: Non specificato
Dimensione 3.81 MB
Formato Adobe PDF
3.81 MB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/20.500.11767/123249
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 1
  • ???jsp.display-item.citation.isi??? 1
social impact