Structures and thermoelectric properties of the infinitely adaptive series(Bi2)m(Bi2Te3

Engineering the topological surface states in the(Sb2)m−Sb2Te3(m=0Johannsen1, Autès2, Crepaldi3 et al. 2015Phys. Rev. B201200View full textAdd to dashboardCite

“…Common strategies for achieving such a control involve chemical substitution and adsorbate doping [9][10][11][12][13]. Alternatively, it has been proposed that multilayer heterostructures could be used to obtain artificial TIs with tunable properties defined by the stacking sequences of the constituent two-dimensional building blocks [14][15][16].In this Rapid Communication, we demonstrate the possibility of TSS band-structure engineering in the naturally occurring homologous series of topological superlattices (Sb 2 ) m -(Sb 2 Te 3 ) n composed of Sb 2 bilayers (BLs) and Sb 2 Te 3 quintuple layers (QLs) [17,18]. This series enables a systematic investigation of the evolution of topological properties as a function of the stacking sequence of the constituent building blocks.…”

“…In this Rapid Communication, we demonstrate the possibility of TSS band-structure engineering in the naturally occurring homologous series of topological superlattices (Sb 2 ) m -(Sb 2 Te 3 ) n composed of Sb 2 bilayers (BLs) and Sb 2 Te 3 quintuple layers (QLs) [17,18]. This series enables a systematic investigation of the evolution of topological properties as a function of the stacking sequence of the constituent building blocks.…”

“…This provides for an "infinitely adaptive series" of * marco.grioni@epfl.ch distinct compounds between the end member compositions Sb 2 Te 3 (m = 0) and Sb (n = 0) [17][18][19][20] that are known to be a TI and a topological semimetal, respectively [21][22][23][24][25][26][27]. Early experiments assessed the topological nature of bulk Sb and Sb-Bi alloys [21,22].…”

“…Spin-orbit effects were accounted for using fully relativistic norm-conserving pseudopotentials acting on valence electron wave functions represented in the two-component spinor form [34] BLs between QLs in the latter compound [17]. While the covalent bonding within QLs and BLs is strong, the interaction between the neighboring building blocks is of the much weaker van der Waals type [17,18]. As a consequence, the natural cleaving plane in Sb 2 Te 3 is located between the QLs and the cleaved surface is always Te terminated.…”

“…Samples were cleaved in ultrahigh vacuum at ambient temperature and immediately transferred to the measurement position, where they were held at 100 K. The first-principles calculations were performed within the density functional theory (DFT) framework employing the generalized gradient approximation (GGA) as implemented in the QUAN-TUM ESPRESSO package [33]. Spin-orbit effects were accounted for using fully relativistic norm-conserving pseudopotentials acting on valence electron wave functions represented in the two-component spinor form [34] BLs between QLs in the latter compound [17]. While the covalent bonding within QLs and BLs is strong, the interaction between the neighboring building blocks is of the much weaker van der Waals type [17,18].…”