Figure 2: Electronic roughness and the opening of a ‘pseudo’-gap within a 7.58 a0 superlattice unit cell.
From: Bond competition and phase evolution on the IrTe2 surface
(a) Atomically resolved image of IrTe2 surface at 77 K, displays clear signs of surface modulation periodicity of 7.58 a0. The surface unit cells are marked by a red parallelogram. The setup conditions for imaging were a sample-bias voltage of −200 mV, a tunnelling current of 0.1 nA with the scan range of 24 × 9 nm2. (b,c) Zoom-in highly resolved STM images at +200 mV (b) and −200 mV (c) sample biases, reveal the atomic structure within a UC of surface superlattice. (d) A series of dI/dV spectra acquired along the blue line in a. The highlighted red curves locate on the top of brightest atomic rows, exhibiting electronic states suppression around the Fermi level. The red shaded area highlights the evolution from a ‘bump’ in local density of states (LDOS) to a suppressed zero-bias DOS. Here, all spectra were taken at 77 K with a bias of −100 mV and a tunneling current of 0.1 nA. Bias-modulation amplitude was set to 5 mVr.m.s..
