Structural and Optical Properties of Co2+-Doped PbSe Nanocrystals in Chalcogeneide Glass Matrix

Semimagnetic chalcogeneide Pb1–xCoxSe nanocrystals were successfully synthesized by a fusion protocol in a glass matrix and characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), magnetic force microscopy (MFM), and optical absorption (OA) techniques. XRD, TEM, and MFM measurements show that the as-produced Pb1–xCoxSe magnetic nanocrystals are single phases, nanosized, and crystallized in rock-salt structures. The OA spectra and crystal field theory indicate that part of Co2+ is incorporated in the tetrahedral site (Td) into PbSe nanocrystals, presenting characteristic structures in the visible and near-IR electromagnetic spectral range. The crystal field strength and Racah parameters are estimated for the tetrahedral coordinated Co2+ ions into PbSe nanocrystals.