Quantitative Analysis of Weak Antilocalization Effect of Topological Surface States in Topological Insulator BiSbTeSe₂

Abstract

Quantitative analysis of the weak antilocalization (WAL) effect of topological surface states in topological insulators is of tremendous importance. The major obstacle to achieve accurate results is how to eliminate the contribution of the anisotropic magnetoconductance of bulk states when the Fermi level lies in bulk bands. Here, we demonstrate that we can analyze quantitatively and accurately the WAL effect of topological surface states in topological insulator, BiSbTeSe2 (BSTS), by measuring the anisotropic magnetoconductance. The anomalous conductance peaks induced by the WAL effect of topological surface states of BSTS together with the anisotropic magnetoconductance of bulk states have been observed. By subtracting the anisotropic magnetoconductance of bulk states, we are able to analyze the WAL effect of topological surface states using the Hikami–Larkin–Nagaoka expression. Our findings offer an alternative strategy for the quantitative exploration of the WAL effect of topological surface states in topological insulators.

Accessing topological surface states and negative MR in sculpted nanowires of Bi2Te3 at ultra-low temperature

“…In the literature, MR measurements showing WAL effects were heavily used to prove the transport through TSS 13,14,19,[29][30][31] .…”

“…Our results indicate that LMR (linear magnetoresitance) observed at high temp range (>2K) is not sufficient for accessing the TSS and measurements at ultra low temp give more access to TSS. In the literature, MR measurements showing WAL effects were heavily used to prove the transport through TSS 13,14,19,[29][30][31] .…”

“…The observance of linear MR (magnetoresistance) and negative MR (NMR), their cross over are important for technological applications as well understanding of these MR signatures is a basic research problem and recently it has been subject of intense research [6][7][8][9][10][11][12][13][14] in topological insulator based materials or in strongly correlated systems. NMR has been observed in non-magnetic materials such as Dirac and Weyl semimetals resulting from chiral anomaly 15,16 .…”

Topological surface states in epitaxial (SnBi2Te4)n(Bi2Te3Fragkos1, Baringthon2, Tsipas3 et al. 2021Phys. Rev. Materials122120View full textAdd to dashboardCite

“…9(b)]. While the appearance of a dip in B⊥I is associated with a 2D TSS, the emergence of a similar magnetoresistance dip in parallel magnetic fields is an indication that a WAL effect originating from the bulk SnBi2Te4 contributes to the conductance in addition to TSS [31][32][33].…”

In-depth Analysis of Anisotropic Magnetoconductance in Bi$_2$Se$_3$ thin films with electron-electron interaction corrections

“…Since our observations show the effect of TSSs on the MC for both IP and OOP magnetic field originating from two distinct mechanisms, we now try to probe their combined response on the AMC of Bi 2 Se 3 films. Recently, Hui Li et al [63] studied the AMC of BiSbTeSe 2 thin films, but in their analysis, the WAL contribution of the 2D surface states at IP magnetic field has been neglected. In contrast, our study has shown a considerable IP WAL signal arising from the finite penetration depth of the surface states.…”