ISSN 1062-8738, Bulletin of the Russian Academy of Sciences. Physics, 2011, Vol. 75, No. 5, pp. 707–709. © Allerton Press, Inc., 2011. Original Russian Text © O.S. Ivanova, I.S. Edelman, R.D. Ivantsov, V.N. Zabluda, S.A. Stepanov, S.M. Zharkov, G.M. Zeer, Ya.V. Zubavichus, A.A. Veligzhanin, J. Curely, 2011, published in Izvestiya Rossiiskoi Akademii Nauk. Seriya Fizicheskaya, 2011, Vol. 75, No. 5, pp. 749–751. 707 INTRODUCTION Magnetic nanoparticles, the mechanisms of their formation in different matrices, and the correlation between particle characteristics and the physical prop- erties of substances containing these particles, are one focus of attention in modern physics of magnetic phe- nomena. The possibility of creating magnetic nano- particles in borate glass doped with low concentrations of iron and rare-earth oxides was demonstrated ear- lier; such doping resulted in glass properties typical for a magnetically ordered state [1, 2] and preserved trans- parency in the visible and near infrared spectral ranges. This work was devoted to investigating the structural and magnetic ordering of nanoparticles in a K 2 O–Al 2 O 3 –GeO 2 –B 2 O 3 glass system doped with Fe 2 O 3 and R 2 O 3 (where R denotes Gd, Tb, Dy, Ho, Er, Yb, or Y 2 O 3 and Bi 2 O 3 ) using X-ray diffraction and the spectral dependences of magnetic circular dichroism. EXPERIMENTAL The following initial materials were used in glass synthesis: KNO 3 , Al 2 O 3 , GeO 2 , and H 3 BO 3 . Iron oxide Fe 2 O 3 with a mass concentration of 4.0% and oxides R 2 O 3 with a mass concentration of 1.5–2.0% were added to 100% of the main composition of the charge prior to synthesis. The glass synthesis technology is described in [1]. Glass samples were subjected to addi- tional thermal processing in different regimes. The composition of synthesized glasses was determined using X ray fluorescence analysis. The table gives the concentrations of components of the sample doped with iron and dysprosium oxides. Magnetooptics and Magnetic Ordering in Ferrite Nanoparticles in Glass Doped with Iron and Rare-Earth Elements O. S. Ivanova a , I. S. Edelman a , R. D. Ivantsov a , V. N. Zabluda a , S. A. Stepanov b , S. M. Zharkov a, c , G. M. Zeer c , Ya. V. Zubavichus d , A. A. Veligzhanin d , and J. Curely e a Kirensky Institute of Physics, Siberian Branch, Russian Academy of Sciences, Krasnoyarsk, 660036 Russia b Vavilov State Optical Institute, St. Petersburg, 199034 Russia c Siberian Federal University, Krasnoyarsk, 660041 Russia d National Research Center Kurchatov Institute, Moscow, 123182 Russia e LOMA, Université Bordeaux-1, France e-mail: osi@iph.krasn.ru Abstract—Magnetic circular dichroism and X-ray diffraction were used to investigate the structure and mag- netooptical properties of nanoparticles formed in potassium–aluminum–germanium–boron glass doped with iron and rare-earth elements. It is demonstrated that in thermally processed glass, the main magnetic phase of the formed nanoparticles is γ-Fe 2 O 3 maghemite. DOI: 10.3103/S1062873811050212 Elemental composition of a sample containing Fe and Dy, and our identification of electron transitions using spectra of magnetic circular dichroism Element Concentration Maximum energy, cm –1 Position Transition from 6 A 1 ( 6 S) to state mass atomic B (Kα) 10.58 20.93 24390 Tetrahedral 4 T 2 ( 4 D) or ISCT O (Kα) 37.94 50.73 22470 Octahedral 4 E g ( 4 D) or ISCT Mg (Kα) 0.52 0.46 20830 Octahedral 4 A 1g , 4 E g ( 4 G) Al (Kα) 14.68 11.64 18520 Tetrahedral 4 A 1 , 4 E ( 4 G) K (Kα) 22.18 12.13 16180 Tetrahedral 4 T 2 ( 4 G) Fe (Kα) 2.43 0.93 15820 Tetrahedral 4 T 1 ( 4 G) Ge (Kα) 10.05 2.96 14710 Octahedral 4 T 2g ( 4 G) Dy (Lα) 1.62 0.21 11010 Octahedral 4 T 1g ( 4 G)