E-mail: ltsonev@abv.bg

Education:

Assoc. Prof. in Physics, 1993, Institute of Solid State Physics, Bulgarian Academy of Sciences, Sofia, Bulgaria, research topic: Relief Holographic Diffraction Gratings.

Ph.D. in Physics, 1987, Institute of Solid State Physics, Bulgarian Academy of Sciences, Sofia, Bulgaria, thesis: “Integrated Optical Waveguides and Components”.

M.S. in Physics, 1978, Sofia State University “St. Climent Ohridsky”, Department of Physics, Specialty Solid State Physics, thesis: “Planar Optical Waveguides for Integrated Optics”

Graduated from German Language High School, Sofia, 1973.

Experience:

1978-present: Institute of Solid State Physics, Bulgarian Academy of Sciences, Sofia, Bulgaria.

Research Topics

2008-present: Megalithic structures in Bulgaria – description, systematization, architectural characteristics, archaeo-astronomical orientation, possibilities for Optically Stimulated Luminescence (OSL) dating.

2004-2007: Luminescence characteristics of LiNbO₃ and LiTaO₃ integrated optical waveguides doped with rare-earth ions.

1996-2004: Thermotropic liquid crystals and memory effects.

1989-1995: Relief holographic diffraction gratings – planar and concave configurations.

1978-1988: Planar optical waveguides for integrated optics in soda lime glass and in LiNbO₃ - characterization, passive and active components.

Memberships:

Editorial board of the Journal Archaeoastronomy and Ancient Technology (since 2014)

Publications:

Author and coauthor of over 50 scientific papers, a book chapter and 2 monographs.

Some representative publications:

Mashev L., Tsonev L., Mironov S. et al “Wave-Propagation in Uniaxial Graded-Index Optical Waveguides” – Appl. Phys. 19(1) 1979, pp. 43-46.

Savatinova I., Simova P., Tsonev L. “Losses in Diffused Optical Waveguides” – Appl. Phys. 20(3), 1979, pp. 219-224.

Savatinova I., Simova P., Tsonev L. ‘Propagation Characteristics of Ag⁺ Ion-Exchanged Stripe Waveguides” – Appl. Phys. 22(2), 1980, pp. 237-240.

Tsonev L., Savatinova I., Simova P. “Ti-LiNbO₃ Optical Waveguides – Dependence of Guide Characteristics on Diffusion Time” – Appl. Phys. 24(3), 1981, pp. 205-209.

Loewen E., Popov E., Tsonev L. et al “Experimental Study of Local and Integral Efficiency Behavior of a Concave Holographic Diffraction Grating” – JOSAm 7(9), 1990, pp. 1764-1769.

Tsonev L., Popov E. “Focal Spot Estimation for Concave Diffraction Gratings” – Opt. Commun. 90(1-3), 1992, pp. 11-15.

Tsonev L., Popov E. “Focal Images Formed by a Concave Holographic Grating – a Corroborative Investigation Using 3 Different Techniques” – J. Mod. Optics 39(8), 1992, pp. 1749-1760.

Popov E., Tsonev L. “Concave Gratings” – Chapter 7 in: E.G.Loewen, E.K.Popov “Diffraction Gratings and Applications”, Marcel Dekker Inc. 1997, pp. 253-283.

Petrov M., Tsonev L. “Surface memory effect in nematics with smectic C short-range order and hydrogen bonded molecules” – Liquid Crystals 21(4) 1996, pp. 543-555.

Petrov M., Tsonev L. “The influence of a bulk twist on the surface memorization in the liquid crystal HOBA” - Liquid Crystals 29(5) 2002, pp. 743-754.

Tsonev L. “Luminescent activation of planar optical waveguides in LiNbO3 with rare earth ions Ln(3+) - a review” – Opt. Materials 30(6) 2008, pp. 892-899.

Л.Цонев „Мегалитите в България”, Фараго, София 2010 (monograph).

Л.Цонев, Д.Колев „Мегалитите в България през погледа на един физик” - Светът на физиката 33(2) 2010, стр. 234-256.

Л.Цонев: „Отново за Мадарския конник”, Домоплан, София 2012. (monograph)

Tsonev L., Kolev D. "Bulgarian megaliths: present state and perspectives for further research” - Mediterranean Archaeology and Archaeometry, 12(2) 2012, pp. 15-19 (Journal edited by the Rhodes University, Greece)

Цонев Л. „Гипотеза об астрономической функции подземного колодца сардинского типа в Болгарии” - Archaeoastronomy and Ancient Technologies 1(1) 2013, pp. 89-100.

Tsonev L., Kolev D. “Megalithic Structures and Dolmen Orientation in Bulgaria” – Archaeoastronomy and Ancient Technologies 1(2) 2013, pp.55-84.

Цонев Л. „Топографическая проверка археоастрономической гипотезы о функции подземного колодца сардинского типа в Болгарии” – Archaeoastronomy and Ancient Technologies 2(1) 2014, pp.43-49.

Tsonev L. and Kolev D. “The Sardinian Type Underground Well Temple at Garlo, Bulgaria: an Architectural and Astronomical Survey” – Journal of Astronomical History and Heritage 17(2) 2014, pp. 222-237.

Tsonev L. “Technological Comparison between three Specific Megalithic Monuments on the Balkans and in Caucasus” – Archaeoastronomy and Ancient Technologies, 3(1) 2015, pp. 88-147.

Specific research activities in the frames of the Project Balkan Megaliths (2008-present):

Member of two expeditions investigating megaliths in Bulgaria (collaboration between University of Madrid, Spain; Institute of astronomy and Institute of Solid State Physics at Bulgarian Academy of Sciences, Sofia, Bulgaria) – 2008, 2010.

Founder (2010), developer and editor of the on-line catalogue “Megaliths on the Balkan Peninsula” (www.balkanmegaliths.bgjourney.com). In collaboration with D.Kolev and V.Stoychev.

Scientific photographic exhibition EXPO-1 “Megaliths on the Balkans” 2008.

Presented in Sofia, Yambol (2008), Plovdiv, Velingrad, Svishtov (2009), Lovech, Nikopol (2010), Blagoevgrad (2015).

Scientific photographic exhibition EXPO-2 „Megaliths, Pagan Sanctuaries and Their Continuity in Christian Times” 2014.

Presented in Yambol, Dupnitsa (2014), Sofia, Plovdiv, Svishtov, Blagoevgrad, Stara Zagora and Velingrad (2015).