Investigation of the cobalt ions diffusion processes in calcium orthovanadate crystals

In this work, the high-temperature diffusion doping method was used for introduction of active cobalt ions into calcium orthovanadate Ca₃(VO₄)₂crystals. Experimental samples were made from a nominally pure CVO single crystal obtained by the Czochralski method. The high-temperature diffusion conditions have been optimized to obtain doped crystals of optical quality during annealing in open and closed zones. Diffusion coefficients of cobalt ions (D) were calculated for various conditions: annealing time 24 - 48 hours; temperature range 1150-1300°C; diffusants - oxide compounds of calcium, cobalt and vanadium: Co₃O₄, Ca₁₀Co_0.5(VO₄)₇ and Ca₃(VO₄)2:2wt.%Co₃O₄; diffusion direction is parallel or perpendicular to the CVO crystal optical axis. The calculated values of the diffusion coefficient varied between 2.09·10^-8—1.58·10^-7 cm²/s. The activation energy of the diffusion process was determined to be 2.58±0.5 and 2.63±0.5 eV for the [001] and [100] directions, respectively. The maximum cobalt concentration in doped CVO crystals was 2·10²⁰ cm^–3. The absorption spectrum of diffusion-doped Ca₃(VO₄)₂:Co samples demonstrates the presence of absorption bands characteristic for Co²⁺ and Co³⁺ ions. It was shown that the intensity ratio of the characteristic absorption bands varies depending on the crystal doping method. The optical anisotropy of the crystal increases with dopant concentration increase.

1. Brixner L.H., Flournoy P.A. Calcium orthovanadate Ca3(VO4)2 - a new laser host crystal. Journal of the Electrochemical Society. 1965;112(3):303–308. https://doi.org/10.1149/1.2423528 L. H. Brixner, P. A. Flournoy. Calcium Orthovanadate Ca3 (VO4)2 - A New laser host crystal. Journal of the Electrochemical Society. 1965;112(3):303–308. https://doi.org/10.1149/1.2423528

2. Wu H.-F., Yuan F., Sun Sh., Huang Y., Zhang L., Lin Zh., Wang G. Growth and spectral characteristics of a new promising stoichiometric laser crystal: Ca9Yb(VO4)7. Journal of Rare Earths. 2015;33(3):239–243. https://doi.org/10.1016/S1002-0721(14)60409-9

3. Kosmyna M.B., Nazarenko B.P., Puzikov V.M., Shekhovtsov A.N., Paszkowicz W., Behrooz A., Romanowski P., Yasukevich A.S., Kuleshov N.V., Demesh M.P., Wierzchowski W., Wieteska K., Paulmann C. Ca10Li(VO4)7:Nd3+, a promising laser material: growth, structure and spectral characteristics of a Czochralski-grown single crystal. Journal of Crystal Growth. 2016;445:101–107. https://doi.org/10.1016/j.jcrysgro.2016.04.002

4. Ivleva L.I., Dunaeva E.E., Voronina I.S., Doroshenko M.E., Papashvili A.G. Ca3(VO4)2:Tm3+ - A new crystalline medium for 2-μm lasers. Journal of Crystal Growth. 2018;501:18–21. https://doi.org/10.1016/j.jcrysgro.2018.08.019

5. Ivleva L.I., Dunaeva., E.E., Voronina I.S., Doroshenko M.E., Papashvili A.G., Sulc J., Kratochvíl J., Jelinkova H. Impact of Tm3+/Ho3+ co-doping on spectroscopic and laser properties of Ca3(VO4)2 single crystal. Journal of Crystal Growth. 2019;513:10–14. https://doi.org/10.1016/j.jcrysgro.2019.02.054

6. Frank M., Smetanin S.N., Jelínek Jr.M., Vyhlídal D., Ivleva L.I., Dunaeva E.E., Voronina I.S., Shukshin V.E., Zverev P.G., Kubeček V. Synchronously-pumped, all-solid-state, picosecond Raman laser at 1169 and 1222 nm on single and combined Raman modes in a Ca3(VO4)2 crystal with 30-times pulse shortening down to 1.2 ps. Laser Physics Letters. 2020;17(11):115402. https://doi.org/10.1088/1612-202X/abbedf

7. Glass A.M., Abrahams S.C., Ballman A.A., Loiacono G. Calcium orthovanadate, Ca3(VO4)2 - A new high temperature ferroelectric. Ferroelectrics. 1977;17(1):579–582. https://doi.org/10.1080/00150197808236782

8. Voronina I.S., Voronov V.V., Dunaeva E.E., Iskhakova L.D., Papashvili A.G., Doroshenko M.E., Ivleva L.I. Growth and properties of manganese doped Ca3(VO4)2 single crystals. Journal of Crystal Growth. 2021;555:125965. https://doi.org/10.1016/j.jcrysgro.2020.125965

9. Voronina I.S., Dunaeva E.E., Papashvili A.G., Doroshenko M.E., Ivleva L.I. Modification of calcium orthovanadate single crystal due to cobalt doping. Journal of Crystal Growth. 2023;615(3):127242. https://doi.org/10.1016/j.jcrysgro.2023.127242

10. Bracht H. Diffusion mechanisms and intrinsic point-defect properties in silicon. MRS Bulletin. 2000;25(6):22−27. https://doi.org/10.1557/mrs2000.94

11. Kozlov V.A., Kozlovski V.V. Doping of semiconductors using radiation defects produced by irradiation with protons and alpha particles. Semiconductors. 2001;35:735–761. https://doi.org/10.1134/1.1385708

12. Mirov S.B., Fedorov V.V., Martyshkin D.V., Moskalev I.S., Mirov M.S., Gapontsev V.P. Progress in mid-IR Cr2+ and Fe2+ doped II-VI materials and lasers [Invited]. Optical Materials Express. 2011;1(5):898–910. https://doi.org/10.1364/OME.1.000898

13. Vaksman Yu.F., Pavlov V.V., Nitsuk Yu.A., Purtov Yu.N., Nasibov A.S., Shapkin P.V. Optical absorption and chromium diffusion in ZnSe single crystals. Semiconductors. 2005;39(4):377–380. https://doi.org/10.1134/1.1900247

14. Rodin S.A. Diffusion doping of CVD-ZnSe with Cr2+ ions. Diss. Cand. Sci. (Chem.). Nizhnii Novgorod; 2018. 129 p. (In Russ.)

15. Sorokina T. Cr2+-doped II-VI materials for lasers and nonlinear optics. Optical Materials. 2004;26(4):395–412. https://doi.org/10.1016/j.optmat.2003.12.025

16. Schmidt R.V., Kaminow I.P. Metal-diffused optical waveguides in LiNbO3. Applied Physics Letters. 1974;25(8):458–460. https://doi.org/10.1063/1.1655547

17. Baumann I., Brinkmann R., Dinand M., Sohler W., Beckers L., Buchal C., Fleuster M., Holzbrecher H., Paulus H., Müller K.-H., Gog T., Materlik G., Witte O., Stolz H., von der Osten W. Erbium incorporation in LiNbO3 by diffusion-doping. Applied Physics A. 1996;64:33–44. https://doi.org/10.1007/s003390050441

18. Jiménez-Melendo M., Haneda H., Nozawa H. Ytterbium cation diffusion in yttrium aluminum garnet (YAG) - Implications for creep mechanisms. Journal of American Ceramic Society. 2001;84(10):2356–2360. https://doi.org/10.1111/j.1151-2916.2001.tb01014.x

19. Hettrick S.J., Wilkinson J.S., Shepherd D.P. Neodymium and gadolinium diffusion in yttrium vanadate. Journal of the Optical Society of America B. 2002;19(1):123–124. https://doi.org/10.1364/JOSAB.19.000033

20. Pavlov P.V., Khokhlov A.F. Solid state physics. Moscow: Vysshaya shkola; 2000. 493 p. (In Russ.)

21. Gopal R., Calvo C. The structure of Ca3(VO4)2. Zeitschrift für Kristallographie - Crystalline Materials. 1973;137(1):67–85. https://doi.org/10.1524/zkri.1973.137.1.67

22. Lazoryak B.I. Design of inorganic compounds with tetrahedral anions. Russian Chemical Review. 1996;65(4):287–305. https://doi.org/10.1070/RC1996v065n04ABEH000211

23. Leonidov I.A., Leonidova O.N., Surat L.L., Samigullina R. Ca3(VO4)2–LaVO4 cation conductors. Inorganic Materials. 2003;39(6):616–620. https://doi.org/10.1023/A:1024057405145

24. Rahimi Mosafer H., Paszkowicz W., Minikayev R., Kozłowski M., Diduszko R., Berkowski M. The crystal structure and thermal expansion of novel substitutionally disordered Ca10TM0.5(VO4)7 (TM = Co, Cu) orthovanadates. Dalton Transactions. 2021;50(41):14762–14773. https://doi.org/10.1039/D1DT02446A

25. Galakhov F.Ya. (ed.). State diagrams of refractory oxide systems. Vol. 5. Dual systems. In 4 parts. Leningrad: Nauka; 1987. Part 3. 287 p. (In Russ.)

26. Tolkacheva A.S., Shkerin S.N., Nikonov A.V., Pershina S.V., Khavlyuk P.D., Leonidov I.I. Electrical and thermal properties of Ca5Mg4−xCox(VO4)6 (0 ≤ x ≤ 4), a promising electrode material. Materials Letters. 2021;305:130811. https://doi.org/10.1016/j.matlet.2021.130811

27. Voronina I.S., Dunaeva E.E., Papashvili A.G., Iskhakova L.D., Doroshenko M.E., Ivleva L.I. High-temperature diffusion doping as a method of fabrication of Ca3(VO4)2:Mn single crystals. Journal of Crystal Growth. 2021;563(3):126104. https://doi.org/10.1016/j.jcrysgro.2021.126104

28. Solov'ev S.D., Korablev G.A., Kodolov V.I. Calculation of activation energy for volumetric diffusion and self-diffusion of elements in solids. Chemical Physics and Mesoscopy. 2005;7(1):31–40. (In Russ.)

29. Shannon R.D. Revised effective ionic radii and systematic studies of unteratomic distances in halides and chalcogenides. Acta Crystallographica. Section A, Foundations of Crystallography. 1976; 32(SEP1): 751–767. https://doi.org/10.1107/S0567739476001551