Ag1-xCuxI (x= 0.10, 0.20, and 0.50) thin films with thicknesses upto15 nm produced by thermal co-evaporation onto
glass substrates were systematically iodized and carefully characterized. Optical absorption spectra of uniodized Ag-Cu
films show intense surface plasmon resonance (SPR) features with maxima at 430, 445 and 445 nm for the films of
thickness 5, 10 and 15 nm respectively and a gradual transition to zincblende AgI exciton with optical signatures at 425
nm. Delayed evolution and inhomogeneous broadening of the exciton absorption at 425 nm of the spatially confined γ-
AgI nanoparticles were clearly seen by the development of Z1,2 and Z3 exciton peaks iodization kinetics being controlled
by the as-quenched Ag-Cu clusters. Cu addition not only restricts the particle size, but also favors the island type growth
mode. PL observed at 428 nm shows a thickness and Cu-composition dependent intensity suggesting the involvement of
Frenkel defects in non-radiative recombination.
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