Topological Phases in InAs1−xSbx: From Novel Topological Semimetal to Majorana Wire

TY - JOUR

T1 - Topological Phases in InAs1−xSbx

T2 - From Novel Topological Semimetal to Majorana Wire

AU - Winkler, Georg W.

AU - Wu, Quansheng

AU - Troyer, Matthias

AU - Jeppesen, Peter Krogstrup

AU - Soluyanov, Alexey A.

N1 - [Qdev]

PY - 2016/8/11

Y1 - 2016/8/11

N2 - Superconductor proximitized one-dimensional semiconductor nanowires with strong spin-orbit interaction (SOI) are, at this time, the most promising candidates for the realization of topological quantum information processing. In current experiments the SOI originates predominantly from extrinsic fields, induced by finite size effects and applied gate voltages. The dependence of the topological transition in these devices on microscopic details makes scaling to a large number of devices difficult unless a material with dominant intrinsic bulk SOI is used. Here, we show that wires made of certain ordered alloys InAs1-xSbx have spin splittings up to 20 times larger than those reached in pristine InSb wires. In particular, we show this for a stable ordered CuPt structure at x=0.5, which has an inverted band ordering and realizes a novel type of a topological semimetal with triple degeneracy points in the bulk spectrum that produce topological surface Fermi arcs. Experimentally achievable strains can either drive this compound into a topological insulator phase or restore the normal band ordering, making the CuPt-ordered InAs0.5Sb0.5 a semiconductor with a large intrinsic linear in k bulk spin splitting.

AB - Superconductor proximitized one-dimensional semiconductor nanowires with strong spin-orbit interaction (SOI) are, at this time, the most promising candidates for the realization of topological quantum information processing. In current experiments the SOI originates predominantly from extrinsic fields, induced by finite size effects and applied gate voltages. The dependence of the topological transition in these devices on microscopic details makes scaling to a large number of devices difficult unless a material with dominant intrinsic bulk SOI is used. Here, we show that wires made of certain ordered alloys InAs1-xSbx have spin splittings up to 20 times larger than those reached in pristine InSb wires. In particular, we show this for a stable ordered CuPt structure at x=0.5, which has an inverted band ordering and realizes a novel type of a topological semimetal with triple degeneracy points in the bulk spectrum that produce topological surface Fermi arcs. Experimentally achievable strains can either drive this compound into a topological insulator phase or restore the normal band ordering, making the CuPt-ordered InAs0.5Sb0.5 a semiconductor with a large intrinsic linear in k bulk spin splitting.

U2 - 10.1103/PhysRevLett.117.076403

DO - 10.1103/PhysRevLett.117.076403

M3 - Journal article

C2 - 27563979

SN - 0031-9007

VL - 117

JO - Physical Review Letters

JF - Physical Review Letters

IS - 7

M1 - 076403

ER -