Spatial variation of the surface state onset close to three types of surface steps on Ag(111) studied by scanning tunnelling spectroscopy

Local-strain mapping on Ag(111) islands on Nb(110)

“…7 However, it has been pointed out that the shift of E ss can have different signs around edge dislocations. 8 From the maximal shift of E ss À E F from À65 meV (Ag single crystal) to þ30 meV we obtain a strain ¼ 0:8% from our DFT calculation (Fig. 3) in good agreement with the estimated thermal strain th ¼ 0:66%, Eq.…”

“…The surface state on Ag(111) has been observed frequently in photoemission and STS experiments with E ss À E F % À65 meV and an effective electron mass m à ¼ 0:4 m e (m e : electron mass). [15][16][17][18] A shift of the surface-state band toward higher energy was found for Ag(111) films on Si, 6,7 on Ag(111) close to surface steps, 8 and over buried interfaces. 18 It is attributed to the local change of the electronic band structure of the bulk and surface bands due to lattice strain.…”

“…The sensitivity of the surfacestate energy on strain, i.e., on the local variation of the electronic structure, has been demonstrated earlier. [6][7][8] The obtained strain map is compared with finite-element method (FEM) calculations.…”

“…13 In particular, on Ag (111) they have been identified as split-edge dislocations emerging at the surface. 8 The island has a wedge shape with a thickness that increases from 12 to 17 nm along the horizontal direction (red arrow) due to the parallel alignment of the Ag(111) plane with the Nb(110) plane of the substrate with a miscut of <1 . Apart from the linear defects the surface is atomically flat.…”

Desorption of Water from Distinct Step Types on a Curved Silver Crystal

“…The associated dipole oriented parallel to the surface was predicted to strongly affect adsorption of molecules. Recently, different types of steps on an Ag(111) surface were also shown by STS to affect the local electronic structure in markedly different ways, indicating that all steps are not equal [46].…”