Magnetotransport properties and giant anomalous Hall angle in the half-Heusler compound TbPtBi

Abstract

Magnetic lanthanide half-Heuslers (RPtBi; R being the lanthanide) represent an attractive subgroup of the Heusler family and have been identified as ideal candidates for time reversal symmetry breaking topological Weyl semimetals. In this paper, we present the detailed analysis of the magnetotransport properties of frustrated antiferromagnet TbPtBi. This material shows large, nonsaturating magnetoresistance (MR) with unusual magnetic field dependence. The MR of TbPtBi is significantly anisotropic with respect to the magnetic field, applied along different crystallographic directions and indicates the anisotropic nature of the Fermi surface. The chiral anomaly induced negative longitudinal magnetoresistance confirms the presence of Weyl fermions. At low temperature, Berry phase driven large anomalous Hall conductivity has been observed. The calculated anomalous Hall angle is the largest reported so far.

Exceptionally large anomalous Hall effect due to anticrossing of spin-split bands in the antiferromagnetic half-Heusler compound TbPtBi

“…The reason why we did not use the Hall conductivity data at 50K for normal Hall contribution subtraction is that R0 in the PM state is weakly temperature dependent. Nevertheless, we find ρxy collapses to a linear field The previously reported large θAH for TbPtBi was attributed to the field-induced Weyl state [38]. The main support for this argument is the observation of the negative longitudinal magnetoresistance (LMR), which was interpreted as arising from the chiral anomaly of a fieldinduced Weyl state.…”

“…1d, we present the anomalous Hall angle (θAH = σ /σxx) as a function of the magnetic field. We find the maximal θAH value of this sample to be as large as ~0.68 near 4T at 2K, about 1.8 times of the previously reported θAH (=0.38 [38]) for TbPtBi and ~2-5 times larger than the values seen in GdPtBi (θAH = 0.16-0.32 [44] ). The Hall angle of θAH = 0.38 for TbPtBi was claimed to the largest among other materials [38]; our result thus sets a new record.…”

“…In the Hall effect measurements, we observed an intrinsic AHE, much stronger than that seen in previous studies on TbPtBi [38] and GdPtBi [37,44]. Our measurements were conducted with the magnetic field applied along the [100] axis (inset, Fig.…”

Ferromagnetic phase transition in topological crystalline insulator thin films: Interplay of anomalous Hall angle and magnetic anisotropy

“…The calculated values of θ AH for the ferromagnetic Sn 1−x Mn x Te layers with x = 0.06, 0.07 and 0.08 as a function of T at µ 0 H = 1 T are reported in Fig. 7(a) and the sample with the highest x has at T =1.8 K the greatest value θ AH ∼0.3, higher than the ones reported for the topological ferromagnetic semimetal Fe 3 GeTe 2 [88] and for the half Heusler ferromagnet TbPtBi [89]. The reported θ AH for both Fe 3 GeTe 2 [88] and TbPtBi [89] were measured at µ 0 H 1 T, whereas in the case of the Sn 1−x Mn x Te layers considered here, the estimation of θ AH is carried out for µ 0 H = 1 T. The large value of θ AH for x = 0.08 indicates that the system is insensitive to impurity scattering, in spite of the electronic disorder defined by 1 RRR w.r.t.…”

Multiple metamagnetism, extreme magnetoresistance and nontrivial topological electronic structures in the magnetic semimetal candidate holmium monobismuthide

“…Especially, as a result of the electronic correlation, various exotic physical properties could be expected in the rare-earth-based semimetals. Take RPtBi (R=Nd, Gd) as an example, due to the large exchange field arising from 4f electrons of R ion and the Zeeman splitting in the presence of magnetic field, the bands split and form Weyl points near the Fermi level, which induces negative magnetoresistance, huge anomalous Hall conductivity and planar Hall effect [13][14][15]. As this scenario shows, strong electronic correlations open the possibility of discovering completely new states of matter with unprecedented functionality, which could also be expected in the magnetic rare earth monopnictides.HoBi, which adopts the rocksalt-type structure at room temperature ( figure 1(a)), namely cubic symmetry with space group Fm3m [39], is another representative of the rare earth monopnictide family.…”