Spin-orbit scattering visualized in quasiparticle interference

Abstract

In the presence of spin-orbit coupling, electron scattering off impurities depends on both spin and orbital angular momentum of electrons -spin-orbit scattering. Although some transport properties are subject to spin-orbit scattering, experimental techniques directly accessible to this effect are limited. Here we show that a signature of spin-orbit scattering manifests itself in quasiparticle interference (QPI) imaged by spectroscopic-imaging scanning tunneling microscopy. The experimental data of a polar semiconductor BiTeI are well reproduced by numerical simulations with the T -matrix formalism that include not only scalar scattering normally adopted but also spin-orbit scattering stronger than scalar scattering. To accelerate the simulations, we extend the standard efficient method of QPI calculation for momentum-independent scattering to be applicable even for spin-orbit scattering. We further identify a selection rule that makes spin-orbit scattering visible in the QPI pattern. These results demonstrate that spin-orbit scattering can exert predominant influence on QPI patterns and thus suggest that QPI measurement is available to detect spin-orbit scattering. * kohsaka@riken.jp 1 arXiv:1703.06234v1 [cond-mat.mes-hall]

Quasiparticle interference in ZrSiS: Strongly band-selective scattering depending on impurity lattice site

“…influences the corresponding potential matrix V def (q ) used in the standard T-matrix ap-proach to computing quasiparticle scattering patterns [18,41,42] scattering channels, such as the spin texture of bands, or the variations in sign of the superconducting order parameter, variables grounded in k -space. These observations rely on scattering from various defects providing a predictably uniform view on q-space.…”

“…The relative strength or suppression of various q-vectors is often used to infer attributes of the bands which are subject to selection rules governing scattering from initial to final states. Such selectivity has been exploited to explore the spin texture in spin-momentum-locked bands structures of topological and Rashba systems [4,[14][15][16][17][18], and the symmetry and momentum-dependent sign of the order parameter in unconventional superconductors [1,2,13]. Aside from the special case of scattering from magnetic flux vortices, which are known to have scattering properties qualitatively different from simple Coulomb potentials [13], impurities have until recently been treated as generic scattering centers, albeit with a relative scattering strength depending on the orbital character of the scattered band, or the different degrees to which impurity lattice sites coincide with a particular band's spatial charge density [16,17].…”

kz Selective Scattering within Quasiparticle Interference Measurements of FeSe

“…The removal of states "by hand", makes this model highly phenomenological, however, within the energy region of ±50 meV, this approach quantitatively reproduces the experimental band dispersions measured by ARPES experiments on detwinned crystals [17][18][19]. The calculation of the local density of states (LDOS), N (r, ω), measured by QPI experiments, has been discussed extensively within the literature [14,26,27]. Here we employ the same T-matrix formalism [28], however, we extend the definition to include out-of-plane scattering vectors.…”

Friedel oscillations in 2D electron gas from spin-orbit interaction in a parallel magnetic field

“…13 The FO near an individual point defect in 2D electron gas with Rashba SOI 18,19 were experimentally observed in Refs. [14][15][16][17], and in this case a rather large number of theoretical works [20][21][22][23][24][25][26][27] were devoted to the analysis of the oscillatory dependence of the LDS. The LDM was theoretically studied in Ref.…”