Surface states induced weak anti-localization effect in Bi_0.85Sb_0.15 topological single crystal

Abstract

We report, an experimental evidence of surface states (SS) driven magneto-transport in a Bi0.85Sb0.15 single crystal. Detailed high field (up to 12T) and low temperature (down to 2K) magneto-transport measurements are been carried out on the studied Bi0.85Sb0.15 single crystal. The phase, composition and Raman modes are studied through X-ray diffraction, Energy dispersive X-ray, and Raman spectroscopy. The obtained crystal shows non-saturating magnetoresistance (≈ 4250%) at 2K and 12T, along with the existence of weak-anti localization (WAL) effect at around zero magnetic field. Further, the Hikami-Larkin-Nagaoka (HLN) analysis is performed to analyse the WAL effect. The prefactor (α) and phase coherence length (L) are deduced at various temperatures, which signified the presence of more than one conduction channel in the studied Bi0.85Sb0.15 single crystal. The effect of quantum scattering, bulk contribution from underneath the surface states and defects are been studied by adding various field dependent quadratic, linear and constant terms to the SS driven HLN equation. Various possible scattering mechanism are studied by analysing the temperature dependence of the phase coherence length. Angle dependent magneto-conductivity of the studied Bi0.85Sb0.15 single crystal clearly confirmed the surface states dominated transport in present crystal.

Lattice Dynamics, Transport and Thermoelectric Properties of Bi-Sb Alloys Obtained by Mechanical Alloying and Spark Plasma Sintering

“…However, Sultana et al found an increase in the frequency of the A 1g with Sb content [56], in contrast with our work and the early studies [54,55]. We note that Kumar et al [59] found lower frequencies for both modes in the case of Bi 0.85 Sb 0.15 alloys than in our work and in other works. This might be explained by the heating of the sample due to too large laser power used in their experiments.…”

Chiral anomaly and Weyl orbit in three-dimensional Dirac semimetal Cd3As2 grown on Si

“…The decrease of α as the temperature increases is consistent with the previous research on other topological materials [39,45]. According to the Nyquist theory, the relation between L f and the temperature caused by electron-electron (e-e) interactions should solely be L T 1 2 µ f -/ for a quasi-2D system [43,46]. In our case, however, L f is not proportional to T .…”

“…The temperature-dependent factor α shall be equal to 1/2 for a 2D conducting system. However, as shown in figure 4(b), the relatively large α indicates the contribution from the bulk and that from the surface states are both involved in the transport event [40][41][42][43][44]. The decrease of α as the temperature increases is consistent with the previous research on other topological materials [39,45].…”

Understanding the Highly Reversible Potassium Storage of Hollow Ternary (Bi-Sb)2S3@N-C Nanocube

“…16, which are indexed to the (003) plane of (Bi,Sb) alloy resulting from the in situ alloying of Bi and Sb. These two adjacent peaks are ascribed to the alloying of Bi/Sb in arbitrary ratios so that there is a slightly difference in interplanar spacing . The above mentioned results indicate the gradual phase transitions from the K x (Bi-Sb) 2 S 3 to K x S and (Bi,Sb) alloy.…”