Semiconductor Physics, Quantum Electronics & Optoelectronics. 2014. V. 17, N 1. P. 041-045.
Comparative studies of optical absorption, photoluminescence
and EPR spectra of PbMnI2 bulk layers and nanocrystals 1
Department of Physics of Semiconductors and Nanostructures, Chernivtsi National University,
2, Kotsiubynsky str., 58012 Chernivtsi, Ukraine, e-mail: a.savchuk@chnu.edu.ua Abstract. We report a study of the layered diluted magnetic semiconductor (DMS) Pb1 - x Mnx I2 in 3D bulk layers and nanocrystal form by using optical absorption, photoluminescence and electron paramagnetic resonance (EPR). The samples of the bulk Pb1 - x Mnx I2 crystals with x lying within the range 0 to 0.15 were grown using the Bridgman-Stockbarger technique. The composite nanostructures containing DMS nanocrystals of Pb1 - x MnxI2 were prepared by cooling the boiling saturated aqueous solution to room temperature. The exciton structure of the absorption spectra of nanoparticles exhibits blue shift due to the quantum confinement effect. In photoluminescence spectra of nanocrystals, two main peaks were revealed, which are attributed to the band-edge transitions and defect states. The EPR spectra for bulk layers and nanocrystals consist of an intense broad line and several weak narrow lines that correspond to hyperfine spectra of Mn2+ ions. Keywords:PbMnI2 , diluted magnetic semiconductor, nanoparticle, nanocrystal, optical absorption. Manuscript received 28.11.13; revised version received 24.01.14; accepted for publication 20.03.14; published online 31.03.14.
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