Journal of Nuclear Science, Engineering and Technology (JONSAT)
In cooperation with the Iranian Nuclear Society

Single Crystal Growth of LiF with OH- and Mg2+ Activators and Evaluation of Optical Characteristics of Color Centers Induced by Ionizing γ- Radiation

Document Type : Research Paper

Authors

Z Dorriz
H Faripour
H Kalbasi
M Esmaeilnia
R Khatiri
E Jangjoo
N. A Akbari
Abstract
Crystal of LiF were grown by a home-made Czochralski system using MgF2 (0.05%), LiOH (0.1%) and Li2CO3 (0.05%) powders as the impurities after purification by the zone-melting method. Another crystal was  also grown with raw materials with the normal purity of 99.995%. The grown crystals were found to be colorless and transparent with no cracks. In order to obtain a high concentration of F2+ centers and small concentration of colloids and parasitic aggregate centers, the grown crystals were subjected to the multi-step ionizing irradiation treatments. At the same time, maintaining the highest possible density of F2+-like centers and small cluster centers caused  the effective thermal stability of F2+- centers and in particular reduced the formation of the electron color centers which improved the stability of the optical features of the modified LiF:F2+** crystals. As a result, acting as a color center laser medium. A comparing of the features of crystals shows that their optical characteristics are the same as the other samples. The XRD properties of the grown crystals were also investigated for the comparison. They indicated the Faced-Centered Cubic (FCC) structures of the crystals. In addition, the inductively coupled plasma (ICP) analysis was used to measure the Mg2+ ion concentration. The emergence of OH- peaks was specified by a FTIR spectrophotometer. In a long run, the spectroscopic characteristics of the new F2+- centers in LiF:OH, Mg crystals were also studied.
 

Keywords

Crystal Growth
Optical Properties
Ionizing Radiation
Lithium Floride
Color Centers
 
[1] Z. Dorriz, Luminescence Materials, Nuclear Science and Technology Research Institute. AEOI (2013).
 
[2] R. Pollock Clifford, Encyclopedia of Laser and optical technology, McGraw-Hill, New York (1992) 9-26.
 
[3] A.H. Kittai, Solid state luminescence, Chapman & Hall (1993).   
 
[4] M. Fox, Optical Properties of Solids, Oxford master series in condensed matter physics (2001).
 
[5] T. T. Basiev, S. B. Mirov, V. V. Osiko,  Room- temperature color center lasers, IEEE J. Quantum Elect. 24 (1988) 1052-1069.
 
[6] V. V. Ter-Mikirtychev, Stable room-temperature tunable LiF: color center laser for 830-1060 nm range pumped by the second harmonic radiation from a neodymium laser, Appl.Opt. 34 (1995) 6114-6117.
 
[7] V.  M.  Khulugurov and B.D.Lobanov, Laser action in the spectral region of 0.84-1.13 𝜇m in the color center LiF-OH crystal at 300 K, Sov. Tech. Phys. Lett. 4 (1978) 595-596.
 
[8] T. T. Basiev, S. B. Mirov and V. V. Ter-Mikirtychev, Two-step photoionization and  photophysics of color centers in LiF crystals, Solid State Lasers and New Laser Materials, 227, Vyacheslav V.Osiko,(ed.) Proc. SPIE 1839 (1992).
 
[9] T. T. Basiev, Yu. K. Voron' ko, S. B. Mirov, Kinetics of accumulation and oscillation of  F2+ color centers in LiFcrystals, Sov. JETP Lett. 30 (1979) 626-629.
 
[10] T. T. Basiev, P. G. Zverev, Temporal and special characteristics of a tunable LiF: F2- color center lasers, Quantum Elect. 27 (1997) 574-578.
 
[11] I. A. Parfianovich, V. M. Julugurov, Luminescence and stimulated emission of color centers in LiF, Bull. Acad. Sci. USSR, Phys. Ser. 43 (1979) 20-27
 
[12] Schneider, US Patent 4, 519, 082 (1985).
 
[13] N.A. Kulagin, Electronic structure of doped and irradiated wide band-gap crystals, Physics  of  Laser Crystals, NATO Sci. Ser. 126 (1999) 135-162.
 
[14] V.V. Fedorov, P.G. Zverev, T.T. Basiev, Broadband lasing and nonlinear conversion of radiation from LiF:F2+ and LiF:F2- color center lasers, Quantum Elect. 31 (2001) 285-289.
 
[15] Z. Dorriz, H. Faripour, H. Kalbasi, M. Esmaeil Nia, R. Khatiri, E. Jangjoo, N. Ali akbari, Single Crystal Growth of LiF with (OH-, Mg2+) Activators and Optical Characteristics of Color Centers Induced by Ionizing γ- Radiation, Nucl. Sci. Tech. Rep. PRD-L2-93-002, (2014).

Home