Optical properties and structure of most stable subnanometer (ZnAs2)n clusters

• Published in: Physica. B, Condensed matter Vol. 368; no. 1-4; pp. 8 - 15
• Main Authors: Yeshchenko, O.A., Dmitruk, I.M., Koryakov, S.V., Galak, M.P., Pundyk, I.P., Hohlova, L.M.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01-11-2005; Elsevier
• Subjects: A. Nanostructures; A. Semiconductors; B. Nanofabrications; Condensed matter: electronic structure, electrical, magnetic, and optical properties; D. Optical properties; Exact sciences and technology; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Optical properties of low-dimensional, mesoscopic, and nanoscale materials and structures; Physics; A. Nanostructures; 78.66.−w; B. Nanofabrications; D. Optical properties; 71.24.+q; A. Semiconductors; Raman spectra; Semiconductor materials; Photoluminescence; Dimensions; Pulsed laser deposition; 78.66.-w A. Nanostructures; Nanostructures; Spectral line shift; Solid clusters; Excitons; Binding energy; Optical properties; Absorption spectra; Zinc arsenides; Nanostructured materials; Nanotechnology
• ISSN: 0921-4526; 1873-2135
• DOI: 10.1016/j.physb.2005.06.030

ZnAs2 nanoclusters were fabricated by incorporation into pores of zeolite Na–X and by laser ablation. Absorption and photoluminescence spectra of ZnAs2 nanoclusters in zeolite were measured at the temperatures of 4.2, 77 and 293K. Both absorption and PL spectra consist of two bands which demonstrate the blue shift from the line of free exciton in bulk crystal. We performed the calculations aimed to find the most stable clusters in the size region up to size of the zeolite Na–X supercage. The most stable clusters are (ZnAs2)6 and (ZnAs2)8 with binding energies of 7.181 and 8.012eV per (ZnAs2)1 formula unit, respectively. Therefore, we attributed two bands observed in absorption and PL spectra to these stable clusters. The measured Raman spectrum of ZnAs2 clusters in zeolite was explained to be originated from (ZnAs2)6 and (ZnAs2)8 clusters as well. The PL spectrum of ZnAs2 clusters produced by laser ablation consists of a single band which has been attributed to the emission of (ZnAs2)8 cluster.