Origin of the butterfly magnetoresistance in a Dirac nodal-line system

Abstract

We report a study on the magnetotransport properties and on the Fermi surfaces (FS) of the ZrSi(Se,Te) semimetals. Density Functional Theory (DFT) calculations, in absence of spin orbit coupling (SOC), reveal that both the Se and the Te compounds display Dirac nodal lines (DNL) close to the Fermi level εF at symmorphic and non-symmorphic positions, respectively. We find that the geometry of their FSs agrees well with DFT predictions. ZrSiSe displays low residual resistivities, pronounced magnetoresistivity, high carrier mobilities, and a butterfly-like angle-dependent magnetoresistivity (AMR), although its DNL is not protected against gap opening. As in Cd3As2, its transport lifetime is found to be 10 2 to 10 3 times larger than its quantum one. ZrSiTe, which possesses a protected DNL, displays conventional transport properties. Our evaluation indicates that both compounds most likely are topologically trivial. Nearly angle-independent effective masses with strong angle dependent quantum lifetimes lead to the butterfly AMR in ZrSiSe arXiv:1904.10123v1 [cond-mat.str-el]

Magnetotransport studies of the Sb square-net compound LaAgSb$_2$ under high pressure and rotating magnetic fields

“…In the normal metallic phase, in contrast, polar spectra show a more complicated structure and obviously depend on the current direction. The polar patterns show butterfly-like shapes in both cases, which are similar to those observed in the other square-net systems [13][14][15][16][18][19][20][21]. In case of I [100], the magnetoresistance takes broad local maxima around ±45 • .…”

“…Another system being intensively studied is M XY (M =Zr, Hf etc., X =Si, Ge, Sn, and Y =S, Se, Te) with a square net composed of X [13][14][15][16][17][18][19][20][21]. The intervention of the nontrivial electronic state in the experimentally observed large nonsaturating magnetoresistance (MR) and high carrier mobility has attracted research interest in these materials.…”

“…The intervention of the nontrivial electronic state in the experimentally observed large nonsaturating magnetoresistance (MR) and high carrier mobility has attracted research interest in these materials. Notably, the MR effect in these * akb@okayama-u.ac.jp materials shows a strong field-angular dependence [13][14][15][16][18][19][20][21], which results in a butterfly-like shape on the polar plot of the resistivity. Although active discussion on the origin of this "butterfly MR" has been performed, whether it involves the nontrivial band structure or can be merely explained by a geometrical effect of the Fermi surface is currently unclear.…”

A two-dimensional topological nodal-line material MgN4 with extremely large magnetoresistance

“…In recent years, an extremely large magnetoresistance (XMR) effect, which is unlike the conventional magnetoresistance phenomenon, has been discovered and it immediately attracted numerous studies due to its potential excellent performance in memory devices and spintronics applications. 1–11 The resistivity of the XMR material increases as the square of the magnetic field, and it can be as high as 10 3 %–10 8 % order without any saturated signal until ultra-high magnetic fields. 12…”

Multiple Dirac Nodes and Symmetry Protected Dirac Nodal Line in Orthorhombic $α$-RhSi

“…This splitting of the Dirac into Weyl nodes has led to the prediction 26 and subsequent observation 27 of new cyclotron orbits involving Fermi arcs on the surface of Cd 3 As 2 with an associated quantum Hall effect 28 . Topological nodal line (NL) systems, or systems where two bands cross forming closed lines within the BZ [29][30][31][32] , is another very active area of research. In general, spin-orbit coupling gaps the NLs unless they are protected by some crystalline symmetry in addition to the inversion and timereversal symmetry [29][30][31] .…”