Magnetic field induced strong valley polarization in the three dimensional topological semimetal LaBi

Abstract

LaBi is a three-dimensional rocksalt-type material with a surprisingly quasi-two-dimensional electronic structure. It exhibits excellent electronic properties such as the existence of nontrivial Dirac cones, extremely large magnetoresistance, and high charge-carrier mobility. The cigar-shaped electron valleys make the charge transport highly anisotropic when the magnetic field is varied from one crystallographic axis to another. We show that the electrons can be polarized effectively in these electron valleys under a rotating magnetic field. We achieved a polarization of 60% at 2 K despite the coexistence of three-dimensional hole pockets. The valley polarization in LaBi is compared to the sister compound LaSb where it is found to be smaller. The performance of LaBi is comparable to the highly efficient bismuth.

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References in corpus (9)

• Valley polarization in MoS2 monolayers by optical pumping
• Valley filter and valley valve in graphene
• Multiple Dirac cones at the surface of the topological metal LaBi
• Compensated semimetal LaSb with unsaturated magnetoresistance
• Observation of a Nematic Quantum Hall Liquid on the Surface of Bismuth
• Topological semimetals and topological insulators in rare earth monopnictides
• Nematic Valley Ordering in Quantum Hall Systems
• Asymmetric mass acquisition in LaBi - a new topological semimetal candidate
• Tuning the electronic and the crystalline structure of LaBi by pressure

Cited by in corpus (5)

• Tunable Electronic Structure and Topological Properties of $LnPn$ ($Ln$=Ce, Pr, Gd, Sm, Yb; $Pn$=Sb, Bi)
• Separation of Electron and Hole Dynamics in the Semimetal LaSb
• Unusual change in the Dirac-cone energy band upon two-step magnetic transition in CeBi
• Anisotropic and extreme magnetoresistance in the magnetic semimetal candidate Erbium monobismuthide
• First-principles study on the electron-phonon coupling and magnetoresistance of LaBi under pressure