Possible origin of linear magnetoresistance: Observation of Dirac surface states in layered PtBi2

DOI: 10.1103/PhysRevB.97.035133

Authors: S. Thirupathaiah (IFW Dresden; Indian Institute of Science) , Y. Kushnirenko (IFW Dresden) , E. Haubold (IFW Dresden) , A. V. Fedorov (IFW Dresden) , E. D. L. Rienks (IFW Dresden) , T. K. Kim (Diamond Light Source) , A. N. Yaresko (Max-Planck-Institute for Solid State Research) , C. G. F. Blum (IFW Dresden) , S. Aswartham (IFW Dresden) , B. Büchner (IFW Dresden) , S. V. Borisenko (IFW Dresden)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Physical Review B , VOL 97

State: Published (Approved)
Published: January 2018
Diamond Proposal Number(s): 15936

Abstract: The nonmagnetic compounds showing extremely large magnetoresistance are attracting a great deal of research interest due to their potential applications in the field of spintronics. PtBi2 is one of such interesting compounds showing large linear magnetoresistance (MR) in both the hexagonal and pyrite crystal structure. We use angle-resolved photoelectron spectroscopy and density functional theory calculations to understand the mechanism of liner MR observed in the layered PtBi2. Our results uncover linear dispersive surface Dirac states at the ¯¯¯ Γ point, crossing the Fermi level with a node at a binding energy of ≈900 meV, in addition to the previously reported Dirac states at the ¯¯¯¯ M point in the same compound. We further notice from our dichroic measurements that these surface states show an asymmetric spectral intensity when measured with left and right circularly polarized light, hinting at a substantial spin polarization of the bands. Following these observations, we suggest that the linear dispersive Dirac states at the ¯¯¯ Γ and ¯¯¯¯ M points are likely to play a crucial role for the linear field dependent magnetoresistance recorded in this compound.

Journal Keywords: Electronic structure; Magnetoresistance; Dirac semimetal; Angle-resolved photoemission spectroscopy; Density functional theory

Subject Areas: Physics, Materials


Instruments: I05-ARPES

Other Facilities: BESSY II

Added On: 22/01/2018 10:16

Discipline Tags:

Quantum Materials Physics Hard condensed matter - structures Materials Science

Technical Tags:

Spectroscopy Angle Resolved Photoemission Spectroscopy (ARPES)