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Berry phase and band structure analysis of the Weyl semimetal NbP.

ABSTRACT: Weyl semimetals are often considered the 3D-analogon of graphene or topological insulators. The evaluation of quantum oscillations in these systems remains challenging because there are often multiple conduction bands. We observe de Haas-van Alphen oscillations with several frequencies in a single crystal of the Weyl semimetal niobium phosphide. For each fundamental crystal axis, we can fit the raw data to a superposition of sinusoidal functions, which enables us to calculate the characteristic parameters of all individual bulk conduction bands using Fourier transform with an analysis of the temperature and magnetic field-dependent oscillation amplitude decay. Our experimental results indicate that the band structure consists of Dirac bands with low cyclotron mass, a non-trivial Berry phase and parabolic bands with a higher effective mass and trivial Berry phase.

SUBMITTER: Sergelius P

PROVIDER: S-EPMC5036179 | biostudies-literature | 2016 Sep

REPOSITORIES: biostudies-literature

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Berry phase and band structure analysis of the Weyl semimetal NbP.

Sergelius Philip P Gooth Johannes J Bäßler Svenja S Zierold Robert R Wiegand Christoph C Niemann Anna A Reith Heiko H Shekhar Chandra C Felser Claudia C Yan Binghai B Nielsch Kornelius K

Scientific reports 20160926

Weyl semimetals are often considered the 3D-analogon of graphene or topological insulators. The evaluation of quantum oscillations in these systems remains challenging because there are often multiple conduction bands. We observe de Haas-van Alphen oscillations with several frequencies in a single crystal of the Weyl semimetal niobium phosphide. For each fundamental crystal axis, we can fit the raw data to a superposition of sinusoidal functions, which enables us to calculate the characteristic ...[more]

PMID: 27667203

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