[1] J. D. B. Bradley, M. Pollnau. Erbium-doped integrated waveguide amplifiers and lasers. Laser Photon. Rev., 5, 368(2011).

[2] A. Shalav, B. S. Richards, M. A. Green. Luminescent layers for enhanced silicon solar cell performance: Up-conversion. Sol. Energy Mater. Sol. Cell., 91, 829(2007).

[3] L. Liu, D. Yan, L. Xu, Z. Zhou, X. Sun, Y. Liu, X. Zong, E. Zhao, J. Ren, J. Zhang, H. Li. Intense and color-tunable upconversion through 980 and 1530 nm excitations. J. Lumin., 224, 117306(2020).

[4] A. M. Dorofeev, N. V. Gaponenko, V. P. Bondarenko, E. E. Bachilo, N. M. Kazuchits, A. A. Leshok, G. N. Troyanova, N. N. Vorozov, V. E. Borisenko, H. Gnaser, W. Bock, P. Becker, H. Oechsner. Erbium luminescence in porous silicon doped from spin-on films. J. Appl. Phys., 77, 2679(1995).

[5] W. Henley, Y. Koshka, J. Lagowski, J. Siejka. Infrared photoluminescence from Er doped porous Si. J. Appl. Phys., 87, 7848(2000).

[6] N. V. Gaponenko, I. S. Molchan, G. E. Thompson, P. Skeldon, A. Pakes, R. Kudrawiec, L. Bryja, J. Misiewicz. Photoluminescence of Eu-doped titania xerogel spin-on deposited on porous anodic alumina. Sens. Actuators A, 99, 71(2002).

[7] N. V. Gaponenko, I. S. Molchan, O. V. Sergeev, G. E. Thompson, A. Pakes, P. Skeldon, R. Kudrawiec, L. Bryja, J. Misiewicz, J. C. Pivin, B. Hamilton, E. A. Stepanova. Enhancement of green terbium-related photoluminescence from highly doped microporous alumina xerogels in mesoporous anodic alumina. J. Electrochem. Soc., 149, H49(2002).

[8] N. V. Gaponenko, I. S. Molchan, S. V. Gaponenko, A. V. Mudryi, A. A. Lutich, J. Misiewicz, R. Kudrawiec. Luminescence of Eu3+ and Tb3+ ions in the structure microporous xerogel/mesoporous anodic aluminum oxide. J. Appl. Spectroscopy, 70, 59(2003).

[9] N. V. Gaponenko, Yu. D. Karnilava, E. I. Lashkovskaya, V. D. Zhivulko, A. V. Mudryi, Yu. V. Radyush, B. A. Andreev, M. V. Stepikhova, A. N. Yablonskiy, S. A. Gusev, R. Subasri, D. S. Reddy. Radiative properties of up-conversion coatings formed on the basis of erbium-doped barium titanate xerogels. Semiconductors, 55, 965(2021).

[10] M. Rudenko, N. Gaponenko, V. Litvinov, A. Ermachikhin, E. Chubenko, V. Borisenko, N. Mukhin, Y. Radyush, A. Tumarkin, A. Gagarin. Structural dependent Eu3+ luminescence, photoelectric and hysteresis effects in porous strontium titanate. Materials, 13, 5767(2020).

[11] J. L. Parsons, L. Rimai. Raman spectrum of BaTiO3. Solid State Commun., 5, 423(1967).

[12] M. L. Moreira, V. M. Longo, Jr. W. Avansi, M. M. Ferrer, J. Andrés, V. R. Mastelaro, J. A. Varela, É. Longo. Quantum mechanics insight into the microwave nucleation of SrTiO3 nanospheres. J. Phys. Chem., 116, 24792(2012).

[13] Yu. I. Yuzyuk. Raman scattering spectra of ceramics, films, and superlattices of ferroelectric perovskites: A review. Phys. Solid State., 54, 1026(2012).

[14] L. F. da Silva, Jr. W. Avansi, J. Andres, C. Ribeiro, M. L. Moreira, E. Longo, V. R. Mastelaro. Long-range and short-range structures of cube-like shape SrTiO3 powders: Microwave-assisted hydrothermal synthesis and photocatalytic activity. Phys. Chem. Chem. Phys., 15, 12386(2013).

[15] U. Balachandran, N. G. Eror. Raman spectra of titanium dioxide. J. Solid State Chem., 42, 276(1982).

[16] J. H. Parker, D. W. Feldman, M. Ashkin. Raman scattering by silicon and germanium. Phys. Rev., 155, 712(1967).

[17] A. Polman. Erbium implanted thin film photonic materials. J. Appl. Phys., 82, 1(1997).

[18] A. J. Kenyon. Recent developments in rare-earth doped materials for optoelectronics. Prog. Quantum Electron., 26, 225(2002).

[19] C. Lei, X.-H. Wei, F. Xu. Effect of Er substituting sites on upconversion luminescence of Er3+-doped BaTiO3 films. Trans. Nonferrous Met. Soc. China, 22, 1156(2012).

[20] J. C. Goldschmidt, S. Fischer. Upconversion for photovoltaics – a review of materials, devices and concepts for performance enhancement. Adv. Opt. Mater., 3, 510(2015).

[21] C. F. Bohren, D. R. Huffman. Absorption and Scattering of Light by Small Particles(1998).

[22] A. I. Kulak, H. Sohrabi Anaraki, N. V. Gaponenko, L. S. Khoroshko, P. A. Kholov, T. F. Raichyonok. Optical characteristics of strontium titanate films formed by sol-gel method on quartz substrates. J. Appl. Spectrosc., 84, 132(2017).

[23] N. I. Stas’kov, A. B. Sotskii, L. I. Sotskaya, I. V. Ivashkevich, A. I. Kulak, N. V. Gaponenko, M. V. Rudenko, A. N. Petlitskii. Optical characteristics of strontium titanate films obtained by the sol–gel method. Opt. Spectrosc., 125, 492(2018).

[24] N. V. Gaponenko. Luminescence of lanthanides from xerogels embedded in mesoporous matrices. Acta Phys. Pol., 112, 737(2007).

[25] H. S. Anaraki, N. V. Gaponenko, V. A. Ivanov. Photocurrent in strontium titanate films on silicon substrates. J. Appl. Spectrosc., 82, 857(2015).