Fig. 3: The orientation-selected spin-polarized edge states of an NiI2 island measured with a Cr tip.
From: Orientation-selective spin-polarized edge states in monolayer NiI2
a SP-STM image of monolayer NiI2 island with stripe modulation (Vs = 0.87 V, Is = 100 pA). b dI/dV spectra taken in the Ni-edge, interior terrace, and I-edge of the NiI2 island. The gray arrow indicates the position of the edge state. c Spin resolved point spectroscopy at the Ni-edge position indicated by red with blue point in (a) for the tip spin state 1 (blue curve) and tip spin state 2 (red curve). The resulting energy-resolved spin polarization is given by the green curve in the bottom panel of (c). Light grey curve represent the background asymmetry obtained over I-edge (reference). d Vertically stacked dI/dV mappings of the same NiI2 island depending on different sample bias voltages. e Spin-polarized tunneling spectra at positive and negative out-of-plane magnetic fields (±6 T) obtained on one position in the inset. The inset indicates the STM image of NiI2 island with Ni-edge. f dI/dV signal as a function of the magnetic field at Vs = 0.8 V. The out-of-plane magnetic field was swept upward (black points) and downward (red points). Error bar indicate the resolution of the differential conductance in the measurement. The hysteresis loop is fitted as dot lines.
