Fig. 3: QPI mappings on hexagonally warped Rashba-split surface states.
a px,py (mj = 1/2)-derived Rashba-split band with unconventional spin topology (red and blue colors are referred to opposite spin directions), dashed and solid black arrow lines indicate intra- (qintra) and interband (qinter) scattering vectors. b Hexagonal CEC with allowed intra- (dashed arrow lines) and interband transitions (solid arrow lines) along \(\overline {{\it{{\Gamma}{\rm{M}}}}}\) (light gray) and \(\overline {{\it{{\Gamma}K}}}\) (dark gray), respectively. c Expected QPI pattern (outlined by solid light and dark gray dots) from only the interband transitions (3 solid arrow lines in b with half magnitude), producing two closed contours (red/blue lines). d Expected QPI pattern (outlined by empty light and dark gray dots) by solely taking the intraband transitions (two dashed arrow lines in b with half magnitude) into account, resulting in a single closed contour (blue line). e–g Top: dI/dU mappings from px,py (mj = 1/2)-derived band with corresponding FT-dI/dU images. The scale bars are 4 nm−1. Bottom: the line profiles along \(\overline {{\it{{\Gamma}{\rm{M}}}}}\) and \(\overline {{\it{{\Gamma}K}}}\) of FT-dI/dU images with an exponential background removed. Two energy-dependent scattering vectors (red/blue arrows) have been identified by employing the Gaussian fits (red/blue lines). (scan parameters: I = 1.0 nA, T = 4.5 K for all dI/dU mappings).
