AVULA BALAKRISHNA

Experienced in developing comprehensive and captivating course content to promote academic growth among students. Implements innovative teaching techniques to enhance classroom learning and encourage active student participation. Demonstrated success in conducting impactful research and contributing to esteemed scholarly publications, showcasing a deep understanding of the subject matter. Additionally, adept at effectively managing demanding research schedules within complex and high-pressure environments. Notably, achieved an h-index of 21, with 1145 citations and 46 publications to credit.

Co-Supervision

Masters in nano science:

T.J. Nkosi Masters (Awarded, 2019) Topic : Nanophosphors, LEDs 1 (Published)

P.M. Maleka Masters (Awarded, 2019) Topic : Nanophosphors, W-LEDs 1 (Published)

M.L.A. Letswalo Masters (Awarded, 2019) Topic : Nanophosphors, LASERS 2 (Published)

A.P. Sefage Masters (Awarded, 2020), Nano powders, display technology, 1 (Published) 1 (Submitted)

K. Morebodi, Masters (Awarded, 2021), Nanomaterials, W-LEDs 2 (Published)

M. Tumelo, Masters (Submitted, 2022), Crystalline materials, Quantum dots, 3 (Submitted)

Doctoral in nanoscience:

M.L.A. Letswalo Doctoral (Awarded, 2022), Nanophosphors, Color-tuning-materials, 2 (Published), 2 (Submitted)

T.G. Mathe Doctoral (Awarded, 2024), Nanophosphors, Up-conversion medical 2 (Published) 2 (Submitted)

University of Johannesburg (UJ), Johannesburg (2018- 2019)

Post-doc. Researcher; Supervisor: Prof. L. Reddy, Prof. P.L. Masiteng 

Nanocrystalline materials:

Substitutional effects of the anionic group systems on photoluminescence (PL) properties of rare-earth ions (Eu3+, Er3+, Yb3+/Eu3+ and Yb3+/Er3+) doped and co-doped Y2O3 nanophosphors, via down and up-conversion: A study on colour-display systems

· Luminescent enhancement of Gd3+activated zinc-sodium-sulphate nanophosphors via the sensitizer (Ce3+, Pr3+, Bi3+) ions for ultraviolet (UV)-B light phototherapy applications

University of the Free State , Bloemfontein (2015- 2018)

Post-doc. Researcher; Supervisors: H.C. Swart, O.M. Ntwaeaborwa 

Phosphors materials:

· Synthesis and structural evolution induced by substitution of designated molybdate sites (MoO4-2) with different anionic groups (BO3-3, PO4-3and SO4-2) in CaMoO4:RE3+ (RE=Rare earth ions) phosphors-A study on color tunable luminescent properties

· Investigation of synthesis and photoluminescence properties of RE3+ ions in different alkaline sodium-phosphate-phosphors

Thin films deposition:

· Synthesis, structures and optical studies of ZnO:Eu3+/Yb3+ thin films: An enhanced monochromatic green emission through cooperative up-conversion upon IR irradiation

· TOF-SIMS induced artificial topographical effects on the ZnO thin films deposited on Si substrates by the sol-gel spin coating technique

Doctoral course; Supervisor: Y.C. Ratnakaram 

· Developed different Pr3+, Nd3+, Sm3+, Eu3+, Dy3+, Ho3+ and Er3+ doped lithium-fluoro-borate glass by melt quenching technique at various temperatures to get high stability and high performance of the different rare-earth ion doped glass materials.

· Analyzed the structural, microstructural, compositional, and optical properties of glass materials using XRD, Raman, SEM, EDS, UV-VIS-NIR, and Visible, NIR emission and decay Spectrofluorimeter.

· Using the Judd-Ofelt (J-O) theory, different radiative properties of laser materials were calculated by means of energy transfer between 4f-infra configurational transitions of rare earth ions and hence the strong color emission (Green, Yellowish-white, orange-red and red) and NIR emission for applications in color emitting LEDs and NIR emission laser technology.

Machaba L. A. Letswalo, Leelakrishna Reddy, Avula Balakrishna*, Hendrik C. Swart, Odireleng M. Ntwaeaborwa, Investigation of red-emitting CaMoO4:Eu3+ phosphor by partitioning of substitutional PO43- ions via solid-state reaction method, Luminescence, 39, 2024, 4905.

T.G. Mathe, A. Balakrishna*, M.A. Mamo, O.M. Ntwaeaborwa, R.E. Kroon, E. Coetsee, H. C. Swart, L. Reddy, A study on the impact of [BO33−], [PO43−] and [SO42−] ions in normal cubic structures via structural and photoluminescence properties of Y2O3: Eu3+phosphors, Journal of Molecular Structure 1299 (2024) 137127.

M.L.A. Letswalo, L. Reddy, A. Balakrishna*, M.A. Mamo, R.M. Erasmus, O.M. Ntwaeaborwa, Multi-colour emission from ZnO[SO4]:Eu2+ nanophosphors: Effects of SO42-and Eu2+ doping concentration, Materials Today Communications 38 (2024) 107944

A.P. Sefage, M.A. Mamo, P.L. Masiteng, A. Balakrishna*, E. Coetsee, H.C. Swart, L. Reddy The concentration effect of Ce3+ ions on the photoluminescence properties of the host sensitized NaMPO4-Ce3+ (M = Mg and Ca) phosphors via solid-state reaction method, Physica B: Condensed Matter 647 (2022) 414383

K.B. Morebodi, L. Reddy, A. Balakrishna*, L.J.B. Erasmus, H.C. Swart, P.L. Masiteng Investigation of photoluminescence properties and energy transfer in Sm3+ and Eu3+co-doped Na2Ca(SO4)2 nanophosphors prepared by combustion technique, Solid State Sciences 134 (2022) 107059.

K. B. Morebodi, L. Reddy, M. L. A. Letswalo, A. Balakrishna*, L. J. B. Erasmus, H. C. Swart, and P. L. Masiteng, Synthesis and investigation of energy transfer mechanism in Sm3+and Eu3+ doped Na6Mg(SO4)4nanophosphors via solution combustion technique, Inorganic and Nano-Metal Chemistry (2022).

M.L.A. Letswalo, L. Reddy, A. Balakrishna*, H.C. Swart, O.M. Ntwaeaborwa The role of sulfate ions on distinctive defect emissions in ZnO:Ce3+ nanophosphors - A study on the application in color display systems, Journal of Luminescence 240 (2021) 118462.

M.LA. Letswalo, L. Reddy, A. Balakrishna*, H.C. Swart and O.M. Ntwaeaborwa, Effect of BO33-ions on photoluminescence of CaMoO4:Eu3+ phosphor, Journal of Vacuum Science & Technology B 37, 012907 (2019) 1-9.

P.M. Maleka, L. Reddy, T.J. Nkosi, A. Balakrishna*, R.E. Kroon, H.C. Swart, O. M. Ntwaeaborwa, Structural and morphological characterization of photoluminescent cerium-doped near UV-blue sodium ortho-phosphate phosphors, Journal of Luminescence 226 (2020) 117409.

L. Reddy, T.J. Nkosi, P.L. Masiteng, A. Balakrishna*, H.C. Swart, O.M. Ntwaeaborwa Violet-blue-shift of emission and enhanced luminescent properties of Ca3(PO4)2:Ce3+phosphor induced by substitution of Gd3+ ions, Current Applied Physics 20 (2020) 696–702.

M.L.A. Letswalo, L. Reddy, A. Balakrishna*, H.C. Swart, O.M. Ntwaeaborwa Influence of SO42-anionic group substitution on the enhanced photoluminescence behaviour of red emitting CaMoO4:Eu3+ phosphor, Journal of Alloys and Compounds 854 (2021) 157022.

A. Balakrishna*, L. Reddy, O.M. Ntwaeaborwa, H.C. Swart, Remarkable influence of alkaline earth ions on the enhancement of fluorescence from Eu3+ ion doped in sodium ortho-phosphate phosphors, Journal of Molecular Structure 1203 (2020) 127375.

A. Balakrishna*, M.M. Duvenhage and H.C. Swart, Surface Chemical characterization of ZnO:Eu3+, Yb3+ spin coated thin films using SEM-CL and Tof-SIMS, Vaccum, 157 (2018) 376-383.

A. Balakrishna*, Trilok K Pathak, E. Coetsee-Hugo, Vinod Kumar, R.E. Kroon, O.M. Ntwaeaborwa,

H.C. Swart, Synthesis, structure and optical studies of ZnO:Eu3+,Er3+,Yb3+ thin films: Enhanced green emission through cooperative up-conversion, Colloids and Surfaces A, 540 (2018) 123-135.

A.Balakrishna*, H.C. Swart, R. Ramaraghavulu, A.K. Bedyal, R.E. Kroon, O.M. Ntwaeaborwa, Structural evolution induced by substitution of designated molybdate sites (MoO−2) with different  anionic groups (BO −3, PO −3 and SO −2) in CaMoO4:Sm3+phosphors-A study on color tunable luminescent properties, Journal of Alloys and Compounds, (2017).

A. Balakrishna*, H.C. Swart, R.E. Kroon, O.M. Ntwaeaborwa, Host sensitized near-infrared emission in Nd3+ doped different alkaline-sodium-phosphate phosphors, Physica B. Condensed matter Physics (2017).

A. Balakrishna*, O.M. Ntwaeaborwa, Study of luminescent behavior and crystal defects of different MNa[PO4]-Dy3+ phosphors (M = Mg, Ca, Sr and Ba), Sensors and Actuators B. Chemical 242 (2017) 305–317.

A. Balakrishna*, S. Babu, Vinod Kumar, O.M. Ntwaeaborwa, Y.C. Ratnakaram, Optical properties and spectroscopic study of different modifier based Pr3+:LiFB glasses as optical amplifiers Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 170 (2017) 167–173.

A. Balakrishna*, Vinod Kumar, Ashwini Kumar, O.M. Ntwaeaborwa, Structural and photoluminescence features of Pr3+-activated different alkaline sodium-phosphate-phosphors, Journal of Alloys and Compounds 686 (2016) 533-539.

A. Balakrishna, D. Rajesh and Y.C. Ratnakaram, Spectroscopic analysis of Ho3+ ion transitions in different modifier oxide based lithium-fluoro-borate glasses, Physica B450 (2014) 58–66.

A. Balakrishna, D. Rajesh and Y.C. Ratnakaram, Structural and optical properties of Nd3+ in lithium fluoro-borate glass with relevant modifier oxides, Journal of Optical Materials 35 (2013) 2670-2676.

A. Balakrishna , D. Rajesh and Y.C. Ratnakaram, Structural and photoluminescence properties of Dy3+ doped different modifier oxide based lithium borate glasses, Journal of Luminescence, 132, (2012) 2984-2991.

D.D. Ramteke, A. Balakrishna , Vijay Kumar and H.C. Swart, Luminescence dynamics and investigation

of Judd-Ofelt intensity parameters of Sm3+ ion containing glasses, Optical Materials 64 (2017) 171-178.

B. Poornaprakash, U. Chalapathi, S.V. Prabhakar Vattikuti, A. Balakrishna , H.C. Swart, Youngsuk Suh, Si-Hyun Park, Journal of Materials Science: Materials in Electronics, Springer (2018).

Y.C. Ratnakaram, A. Balakrishna , D. Rajesh and M. Seshadri, Influence of modifier oxides on spectroscopic properties of Sm3+ doped lithium fluoro-borate glasses, Journal of Molecular Structure, 1028 (2012) 141-147.

Y.C. Ratnakaram, A. Balakrishna , D. Rajesh, Effect of modifier oxides on absorption and emission properties of Eu3+ doped different lithium fluoroborate glass matrices, Physica B 407 (2012) 4303-4307.

Y.C. Ratnakaram, A. Balakrishna , D. Rajesh, Investigations on Influence of modifier oxides on structural, thermal and optical properties of Er3+ doped lithium fluoroborate glass. Journal of Physics and chemistry of Glasses: Europian Journal of Glass Scence Technology B, October 2013, 54 (5), 216–222.

D. Rajesh, A. Balakrishna, and Y.C. Ratnakaram, Spectroscopic investigations on Pr3+ and Nd3+ doped strontium–lithium–bismuth borate glasses, Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 97 (2012) 963–974.

D. Rajesh, A. Balakrishna, Y.C. Ratnakaram, Preparation Luminescence, structural and dielectric properties of Sm3+ impurities in strontium lithium bismuth borate glasses, Optical Materials 35 (2012) 108–116.

S. Babu, A. Balarishna, D. Rajesh, Y.C. Ratnakaram, Investigations on luminescence performance of Sm3+ ions activated in multi- component fluoro-phosphate glasses, Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 97 (2012) 963–974.

M.V. Sasi Kumar, D. Rajesh, A. Balakrishna Y.C. Ratnakaram, Thermal and optical properties of Nd3+ doped lead zinc borate glasses—Influence of alkali metal ions, Physica B 415 (2013) 67.

M.V. Sasi kumar, D. Rajesh, A. Balakrishna, Y.C. Ratnakaram, Optical absorption and photoluminescence properties of Dy3+ doped heavy metal borate glasses – Effect of modifier oxides, J. Molecular Structure 1041 (2013) 100.

D. Rajesh, Y.C. Ratnakaram, M. Seshadri A. Balakrishna , T. Satya Krishna, Structural and luminescence properties of Dy3+ ion in strontium lithium bismuth borate glasses, Journal of Luminescence 132 (2012) 841.

D. Rajesh, M. Dhamodar Naidu, A. Balakrishna, Y.C. Ratnakaram, Ho3+ doped strontium aluminum bismuth borate glasses for green light emission, Luminescence: The Journal of Biological and Chemical Luminescence, Wiley publications.

M. dhamodar Naidu, D. Rajesh, , A. Balakrishna , Y.C. Ratnakaram, Photoluminescence Properties of Eu3+ ion in strontium-aluminium-bismuth-borate glass, J. Rare Earths. 32 (2014) 1131-1138.

A. Balakrishna*, T.G. Mathe, L. Reddy, H.C. Swart and O.M. Ntwaeaborwa Structural and photoluminescent properties of Y2O3, Y2O3-AG: Eu3+ (where AG = BO3-3 , PO4-3and SO4-2) nanophosphors for white-LED applications, SAIP-2022, organized by Nelson Mandela University, South Africa. 

K. B. Morebodi, L. Reddy, M. L. A. Letswalo, A. Balakrishna*, L. J. B. Erasmus, H. C. Swart, and P. L. Masiteng, Investigation of energy transfer mechanism in Sm3+and Eu3+ doped Na6Mg(SO4)4nanophosphors prepared by solution combustion technique, SAIP-2021, organized by North-West University, South Africa. A. Balakrishna*, L. Reddy, H.C. Swart and O.M. Ntwaeaborwa, Composition induced structural evaluation in BO3-3, PO4-3and SO4-2 substituted CaMoO4:Dy3+phosphors for application in White Light LEDs, SAIP-2019, organized by University of Venda, South Africa. 

A. Balakrishna*, E. Coetsee-Hugo, M.M. Duvenhage and H.C. Swart, Surface Chemical characterization of ZnO:Eu3+, Yb3+ thin films on Si (100) substrates using Tof-SIMS, SAIP-2018, organized by University of the Free State, Bloemfontein, South Africa.

A. Balakrishna*, H.C. Swart, R.E. Kroon and O.M. Ntwaeaborwa, Host sensitized near-infrared emission in Nd3+ doped different alkaline-sodium-phosphate phosphors, AMANZI-2017, organized by UFS, Bloemfontein, South Africa.

A. Balakrishna*, Vinod Kumar, Ashwini Kumar, O.M. Ntwaeaborwa, Investigation on Luminescence Properties of Dy3+ Doped different Alkaline based White-light emitting Phosphors, South African Institute of Physics (SAIP-2016) organized by CUT, Cape town, South Africa.

A. Balakrishna*, D. Rajesh and Y.C. Ratnakaram, Spectroscopic investigations on Nd3+ doped lithium-fluoro-borate glass with different modifier oxides for solid state laser applications, International conference on recent advances in Physics (ICRAP 2013) Dec 19-23, 2011 organized by Sri Vidya mandhir Arts & Sceince college, Krishna Giri, Tamilnadu.

A. Balakrishna* , Y.C. Ratnakaram, D. Rajesh and M. Seshadri Influence of modifier oxide on spectroscopic properties of Sm3+ doped lithium fluoroborate glass systems International Conference on Speciality Glass & Optical Fiber: Materials, Technology and Devices (ICGF-2011), August 4-6, 2011, organized by CSIR-CGCRI, Kolkata.

A. Balakrishna*, Y.C. Ratnakaram, D. Rajesh and M. Seshadri Structural and optical properties of Eu3+ doped lithium fluoro-borate glasses containing different modifier oxides International Conference on Materials and Technology (ICMST- 2012), June 10-14, 2012, orgaqnized by St. Thomos College, Pala, Kerala, India

A. Balakrishna*, Y.C. Ratnakaram, D. Rajesh and M. Seshadri Structural and photoluminescence properties of Dy3+ ions in modifier oxide-based lithium fluro-borate glasses, International Conference on Luminescence and its Applications (ICLA-2012) 7-10th, February, 2012 organized by IICT- Hyderabad, India.

A. Balakrishna*, Y.C. Ratnakaram, D. Rajesh, Photoluminescence properties of Ho3+ ion in lithium-fluoro-borate glass containing different modifier oxides 58th DAE Solid State Physics Symposium” December 17 -21, 2013 organized at Thapar University, Patiala.

A. Balakrishna*, Y.C. Ratnakaram, D. Rajesh, Structural, thermal and spectroscopic investigations on Er3+ doped different modifier oxides based lithium fluoro-borate glasses National Conference on Advances in Materials Science and Technologies (AMST - 2012), Kakatiya University, Warangal, A.P., India.

Participated in International work shop on “CrystalGrowth and Characterization of Advanced Materials and Devices” (IWCGCMD), 16-19th December 2012, Crystal growth center, Anna University, Chennai, India.

Participated in “NMISA Basic Laser Safety Course”, 06th August 2015, Central University of Technology (CUT), Bloemfontein, Republic of South Africa.

1) Prof. Y.C. Ratnakaram, Dept. of Physics,

Sri Venkateswara University, Tirupati, India

Tel: +91-9440751615, ratnakaramsvu@gmail.com

2) Prof. O.M.   Ntwaeaborwa, Dept. of Physics,

University of Witwatersrand, Johannesburg, South Africa

Tel: +27 794983514, ntwaeab@gmail.com

3) Prof. H.C.   Swart, Dept. of Physics,

University of the Free State, Bloemfontein, South Africa

Tel: +27 834069449, swarthc@ufs.ac.za

4) Prof. P.L.   Masiteng, Dept. of Applied Physics,

University of Johannesburg, Johannesburg, South Africa

Tel: +27 747591871, plmasiteng@uj.ac.za

I hereby declare that all the details furnished above are true and correct to the best of my knowledge and belief., 

Bengaluru,                                                                                Dr. A. Balakrishna

04/03/25