Anisotropic patterns formed in Ag–As–S ion-conducting amorphous semiconductor films by polarized light

Abstract

Photoinduced surface deformations in ion-conducting Ag-As-S glasses. I. Isotropic deformations produced by small light spots

Photoinduced surface deformations in ion-conducting Ag–As–S glasses. II. Anisotropic deformation produced by large light spots

“…However, the relationship between the expansion phenomenon described in Paper I and a patterning effect previously reported 6 is not clear. In Ref.…”

“…%, which is consistent with the previous work. 6 In contrast, the gross deformation brings about no appreciable Ag concentration changes.…”

“…The appearance of fine deformations is consistent with that reported previously. 6 That is, in the central part of the illuminated spot ͑black region͒ many small fringes exist, the direction of which is nearly parallel to the electric field ͑indicated by double arrow͒, and there exist streaks radiating from the central part to the direction nearly perpendicular to the electric field. In addition, Fig.…”

“…In the previous work, 6 it has been proposed that the fringe accompanying the Ag-content modification appears through the following processes: Incident polarized light is scattered by inhomogeneities such as dust particles on sample surfaces and disordered glassy structures. The feature can be treated using the Mie scattering formulas, in which the scattering is stronger to the directions perpendicular to the electric field of light.…”

“…%. 6 This Ag-content modification can produce expansive forces, because Ag-accumulated phases will expand ͑Paper I͒, while Ag-depleted regions may hold mostly fixed volumes due to the smaller fluidity in amorphous networks in darker regions. Actually, we can see in Fig.…”