Chair of Physical and Colloid Chemistry, Chemical and Technological Institute, Ural Federal University named after the first President of Russia B. N. Yeltsin, Ekaterinburg, Russia

A. S. Korsakov, Senior Lecturer, e-mail: korsa5555@bk.ru
L.V. Zhukova, Chief Researcher, Professor
E. A. Korsakova, Post-Graduate Student
V. V. Zhukov, Senior Researcher
V. S. Korsakov, Candidate for a Master's Degree

By means of differential thermal analysis the new AgBr – TlI system phase equilibrium diagram, including phase transition temperatures and crystal system for TlI modifications, has been studied. The stable substitutional solid solution existence region was then determined. Maximum solubility of TlI in AgBr proved to be 25 wt. %. The eutectic of the above system melts at 160 ^oC and contains 60 wt. % of TlI and 40 wt. % of AgBr. The eutectic position was also confirmed by virtue of Tammann's triangle built by using the peak heights characterizing the solid solution thermal effects for the system under investigation. Improved apparatus KPC-02 for crystal growth implements vertical Bridgman technique with low-frequency axial vibrations being introduced into the melt. It is characterized by the stability of temperature gradient supported, increased grown crystal size, and wide growth rate variation range. The chemical and mechanical treatment method for extrusion billet is also improved, which helps to get rid of undesirable fiber impurities due to reaction atmosphere created in extrusion container. We worked out the growth modes for photostable crystals which the nanocrystalline IR fibers for the widespread use are extruded from. For operating at CO₂-laser wavelength single-mode IR fibers were produced on the basis of structure simulating by Matlab SMTP [1] and fundamental characteristic theoretical calculations. It was found that new single-mode nanostructured IR fibers possess wide transparency range (2.0 – 40.0 μm), increased photostability, in comparison with AgBr – AgCl system, low optical losses in the infrared, high plasticity, non-hygroscopicity and radiation resistance. Properties above are largely due to monovalent thallium iodide introduction into parent silver bromide crystal lattice allowing grain recrystallization of the IR fiber obtained to be blocked.

1. The applied physics group. 2012. Available at : http://www.tau.ac.il/~applphys.
2. Artyushenko V. G., Baskov P. V., Golovanov V. F. et al. Neorganicheskie materialy — Inorganic Materials. 2005. Vol. 41, No. 1. pp. 73–81.
3. Rave E., Ephrat P., Goldberg M., Kedmi E., Katzir A. Silver halide photonic crystal fibers for the middle infrared. Applied Optics. 2004. Vol. 43. pp. 2236–2241.
4. Shalem S., Tsun A., Rave E., Millo A., Nagli L., Katzir A. Silver halide single-mode fibers for the middle infrared. Applied Physics Letters. 2005. Vol. 87, Iss. 9. pp. 091103-1–091103-3.
5. Korsakov A. S., Zhukova L. V., Korsakova E. A., Chazov A. I. Rasplavy — Melts. 2010. No. 6. pp. 76–84.
6. Korsakov A. S., Zhukova L. V. Kristally dlya IK-volokonnoy optiki. Fiziko-khimicheskie osnovy polucheniya kristallov tverdykh rastvorov galogenidov serebra i talliya dlya IK-volokonnoy optiki (monografiya) (Crystals for infra-red fiber optics. Physical and chemical basis of obtaining of crystals of solid solutions of silver and thallium halogenides for infra-red fiber optics (monography)). Saarbrücken : LAP Lambert Academic Publishing, 2011. 152 p.
7. Nanotekhnologiya i fizika funktsionalnykh nanokristallicheskikh materialov (Nanotechnology and physics of functional noncrystalline materials). Tezis doklada X Mezhdunarodnogo seminara (Thesis of a report of the X International seminar). Ekaterinburg, 2005. 175 p.
8. Zhukova L. V., Korsakov A. S., Zharikov E. V., Vrublevskiy D. S., Korsakov V. S. Tsvetnye Metally — Non-ferrous metals. 2010. No. 1. pp. 69–72.
9. Serebra galogenidy (Silver halides). 2012. Available at : http://www.xumuk.ru/encyklopedia/2/4019.html.
10. Fedyushkin A., Bourago N., Polezhaev V., Zharikov E. The influence of vibration on hydrodynamics and heat-mass transfer during crystal growth. Journal of Crystal Growth. 2005. Vol. 275. pp. 1557–1563.