Zheng, W.Schönemann, R.Aryal, N.Zhou, Q.Rhodes, D.Chiu, Y. -CChen, K. -WKampert, E.Förster, T.Martin, T. J.McCandless, Gregory T.Chan, Julia Y.Manousakis, E.Balicas, L.2019-07-262019-07-262018-06-292469-9950https://hdl.handle.net/10735.1/6747We present a detailed quantum oscillatory study on the Dirac type-II semimetallic candidates PdTe₂ and PtTe₂ via the temperature and the angular dependence of the de Haas-van Alphen and Shubnikov-de Haas effects. In high-quality single crystals of both compounds, i.e., displaying carrier mobilities between 10³ and 10⁴ cm²/Vs, we observed a large nonsaturating magnetoresistivity which in PtTe₂ at a temperature T=1.3 K leads to an increase in the resistivity up to (5×10⁴)% under a magnetic field μ₀H=62 T. These high mobilities correlate with their light effective masses in the range of 0.04 to 1 bare electron mass according to our measurements. For PdTe₂ the experimentally determined Fermi surface cross-sectional areas show excellent agreement with those resulting from band structure calculations. Surprisingly, this is not the case for PtTe₂, whose agreement between calculations and experiments is relatively poor even when electronic correlations are included in the calculations. Therefore, our study provides strong support for the existence of a Dirac type-II node in PdTe₂ and probably also for PtTe₂. Band structure calculations indicate that the topologically nontrivial bands of PtTe₂ do not cross the Fermi level. In contrast, for PdTe₂ the Dirac type-II cone does intersect, although our calculations also indicate that the associated cyclotron orbit on the Fermi surface is located in a distinct k_z plane with respect to that of the Dirac type-II node. Therefore, it should yield a trivial Berry phase.en©2018 American Physical SocietySuperconductivityCondensed MatterPalladium(II) TelluridePlatinum(IV) TellurideFermi surfacesarticleZheng, W., R. Schönemann, N. Aryal, Q. Zhou, et al. 2018. "Detailed study of the Fermi surfaces of the type-II Dirac semimetallic candidates XTe2 (X =Pd, Pt)." Physical Review B 97(235154): 1-10, doi:10.1103/PhysRevB.97.23515497235154