Bulgarian Institute of Solid State Physics
Bulgarian Academy of Sciences
English

Home

Physicists

Funds

Donors

Exhibitions

Symposium

Jubilee

News

Video

References

Links

Services

Bookstore


Memoirs

Created 19.2.2018
Updated 26.11.2025

Protocols
Records
Sertificates
Donor
LOZAN SPASSOV SLAVOV
Emeritus Professor, Sc.D., Corresponding Member of BAS

Born in vilage Paunovo, Sofia region (18.02.1938)

Education

He studied physics at the Sofia University (1958-1963)

L. Spassov defended PhD (1977) and ScD (1989) at the Bulgarian Academy of Sciences Institute of Solid State Physics (ISSP)

He specialised in London (1979) and Tokyo (1971-1973, 1985)

Professional Experience

He started to work at the Factory for Electronic Conversion Elements (ZEPE) (1964-1976) where he supervised first Bulgarian quartz resonators production (ZEPE)

At the ISSP, he headed Acoustoelectronics Laboratory until his retirement

Research

He investigated acoustic waves distribution in piezoelectric quartz

He investigated synthetic monolitic quartz growth

Professor Lozan Spassov developed industrial implementation quartz resonators and filters used in telecomunication

He created new sensitive pieso-resonant quarz sensors for temperature, humidity, mass, velosity in liquid and gaseous fluids used to detect mercury polution registration, ammonia vapor, nitrogen oxides and many other toxins in inveronment

He offered a new method for unique ultra-miniature quarz resonators creating with thermosensitivity (4,2 K - 450 K) and high stability (more than 10 years) independent of electric, magnetic and radiation fields

Awarded

First rize in the field of scientific and technical applied research, Joint Institut of Nuclear Research, Dubna, Russia (2001)

Publications
He has 10 patents, over 140 publications and more then 20 construction and technological developments

  1. L. Spassov, High sensitive quartz temperature sensors, Engineering Sciences, LVIII (3) 16-27 (2021)

  2. L. Spassov, Contribution of Physics in research and technology of quartz and quartz devices in Bulgaria, 3rd National Congress on Physical Sciences, 29 Sep. – 2 Oct. 2016, Sofia (2016) 1-12

  3. P. Stefanov, M. Shipochka, P. Stefchev, Z. Raicheva, V. Lazarova, L. Spassov, XPS characterization of TiO2 layers deposited on quartz plates, Journal of Physics, Conference Series, 100 (1) 012039 (2008)

  4. V. Georgieva, L. Spassov, D. Spassov, N. Donkov, P. Petkovv, Tantalum pentoxide - based quartz crystal microbalance for NH3 detection, Journal of Optoelectronics and Advanced Materials, Vol. 9 (2) 252-255 (2007)

  5. V. Georgieva, P. Stefchev, P. Stefanov, L. Spassov, Z. Raicheva, K. Ivanova, Liquid Phase Deposition of Thin Titanium Dioxide Films for NH3 Detection, 6-th International Conference of the Balkan Physical Union, 22-26 August 2006, Istanbul-Turkey, AIP Conference Proceedings (vol. 899) p. 732 (2007)

  6. B. Dulmet, Yu. Lazarov, L. Spassov, P. Tinguy, Last improvements in the analysis of resonant strip sensors, Proc. of the 2007 IEEE International Frequency Control Symposium jointly with the 21-th EFTF, Geneva, Switzerland, pp.363-368 (2007)

  7. P. Stefanov, M. Shipochka, P. Stefchev, Z. Raicheva, V. Lazarova (Georgieva), L. Spassov, XPS Characterization of TiO2 Layers Deposited on Quartz Plates, International Vacuum Congress and European Conference of Surface Science, Sweden, Stockholm 2-6.07.2007

  8. V. Georgieva, L. Spassov, N. Donkov, P. Petkov, M. Atanasov, Detection of NH3 by quartz crystal microbalance coated with Ta2O5, Plasma Process. Polym. (3) 209-213 (2006)

  9. B. Dulmet, Yu. Lazarov, L. Spassov, Semi Analitical Modelling of Thermosensitive Strip Resonators, Proc. of the 20th European Frequency and Time Forum, Braunschweig, Germany, 27-30 March 2006

  10. V. Gadjanova, R. Velcheva, L. Spassov, Yu. Lazarov, L. Vergov, B. Dulmet, Single Point Calibration and Investigation of Thermosensitivity, Thermal Response, Proc. of the 20th European Frequency and Time Forum, Braunschweig, Germany, 27-30 March 2006

  11. V. Georgieva, L. Spassov, D. Spassov, N. Donkov, P. Petkov, Tantalum Pentoxide - Based Quartz Cristal Microbalance for NH3 Detection, Journal of Optoelectronics and Advanced Materials (2006)

  12. V. Georgieva, P. Stefchev, P. Stefanov, L. Spassov, Z. Raicheva, K. Ivanova, Liquid Phase Deposition of Thin Titanium Dioxide Films for NH3 Detection, Proc. of the 6th International Conference of the Balkan Physical Union, Instanbul- Turkey, 22-26 August 2006

  13. B. Dulmet, L. Spassov, R. Bourquin, A. Ivan, Ts. Angelov, J. Lazarov, Design of a new miniature resonant temperature sensor in NLC-cut of quartz, Proc. of the 19th European Frequency and Time Forum, Besancon, France, 21-24 March (2005) 621-628

  14. M. Paroha, E. Benes, L. Spassov, B. Bode, R. Schnitzer, M. Groschl, Prototypes of resonant piezoelectric BAW sensors for various physical measurement, Proc. of the 2nd Congress of Alps Adria Acoustic Association, June 23-24, 2005, Opatia, Croatia

  15. R. Schnitzer, M. Groschl, L. Spassov, E. Benes, Temperature sensitive quartz crystals for high precision dew point hygrometry, Proc. of the 2nd Congress of Alps Adria Acoustic Association, Opatia, Croatia, 23-24 June 2005

  16. L. Spassov, From bilateral project Thermosensitive quartz resonators at cryogenic temperatures in the frame of BAS-CNRS agreement to successful research project QxSens from 5-th FP of EC, Scientific session of 40 anniversary CNRS-BAS scientific cooperation , Sofia, 14-17 November 2005

  17. L. Spassov , Thermosensitive quartz resonators, NEWS , Bulgarian Academy of Sciences, Vol. 9 (2005)

  18. V. Georgieva, P. Stefchev, P. Vitanov, L. Spassov, Quqrtz Resonator with Thin TiO2 for NH3 Detection, 13th International School on Vacuum, Electron and Ion Technologies, 15-19 September 2003, Varna, Bulgaria, Vacuum (76) 203–206 (2004)

  19. V. Georgieva, L. Spassov, E. Manolov, Influence of the surface roughness on the sorption sensitivity of quartz resonators, EFTF 2004, Guildford, UK, 5-7 April 2004

  20. B. Dulmet, L. Spassov, Ts. Angelov, Finite element analisies (FEA) for a new design of NLC-cut quartz crystal resonant temperature sensor, Proc. of the 18-th EFTF, Univ. of Surrey, UK, 5-7 April 2004

  21. L. Spassov, R. Velcheva, L. Vergov, R. Bourquin, A. Ivan, B. Dulmet, “Investigations of electrical parameters and mode patterns of NLC-cut quartz resonator at low temperature”, Proc. of the 18-th EFTF, Univ. of Surrey, UK, 5-7 April 2004

  22. V. Georgieva, Ts. Angelov, L. Vergov, L. Spassov, G. Beshkov, EFTF, Neushatel (2001) p. 348

  23. V. Georgieva, D. Dimitrov, G. Beshkov, L. Spassov, Proc. of EFTF, Torino (2000) p. 225

  24. V. Georgieva, E. Radeva, L. Spassov, Vacuum (58) p. 315 (2000)

  25. V. Georgieva, L. Spassov, V. Georgiev, IEEE IFCS, Besanson (1999) p. 1086

  26. L. Spassov, V. Georgieva, M. Marinov, IEEE IFCS, Besanson (1999) p. 481

  27. L. Spassov, V. Lazarova, E. Manolov, Procidings of ISSWAS-4, St. Petersburg (1998) p. 98

  28. E. Radeva, V. Georgiev, L. Spassov, N. Koprinarov, S. Kanev, Humidity adsorptive properties of thin fullerene layers studied by means of quartz micro-balance, Sensors and Actuators B: Chemical, 42 (1) 11-13 (1997)

  29. L. Spassov, E. Yossiffov, V. Georgiev, L. Vergov, A rotated Y-cut quartz resonator with a linear temperature–frequency characteristic, Sensors and Actuators A: Physical, 58 (3) 185-189 (1997)

  30. V. Lazarova, L. Spassov, V. Georgiev, S. Andreev, E. Manolov, L. Popova, Vacuum (47) 1423 (1976)

  31. M. Onoe, L. Spassov, J. of Industrial Sci, University of Tokyo, Vol. 25, Nr. 12 (1973); Compt.Rend.Acad.Bu1g. Sci., Vo1.27, Nr 4 (1974)

  32. E. Radeva, D. Tsankov, K. Bobev, L. Spassov, Fourier transform infrared analysis of hexamethyldisiloxane layers obtained in low-frequency glow discharge, Journal of applied polymer science, 50 (1) 165-171 (1993)

  33. L Spassov, Acoustoelectronics in Bulgaria: research and development, IEEE 1992 Ultrasonics Symposium Proceedings, 178-188 (1992)

  34. V. Kutepova, L. Spassov, A. Kozlov, Comptes Rendus de 1 'Academie Bulgare de Sciences (43) 11 (1990)

  35. M. Borissov, L. Spassov, BG patent 75536 / 30.06.1987

  36. M. Borissov, L. Spassov, BG patent 81377 / 07.10.1987

  37. M. Borissov, L. Spassov, E. Yossifov, K.Grancharov, Proceedings of the 5th Conference on Electromechanical Devices and their Applications, November Tokyo, Japan (1987)

  38. M. Borissov, L. Spassov, E. Yossifov, A. Balabanova, E. Radeva, Electronics Letters, 23 (4) (1987)

  39. M. Borissov, I. Avramov, D. Dechev, E. Yossifov, K. Gruncharov, L. Spassov, 620 MHz and 1027 MHz surface acoustic waves oscillators, In: Proceedings of the I International symposium on surface waves in solids and layered structures, Novosibirsk (1) 327–331 (1986)

  40. M. Borissov, L. Spassov, E. Yosiffov, K. Grancharov, Studies on the hydrothermal growth of piezoelectric quartz, In: Proc?eding of 5th meeting of the Committee on electromechanical devices and their applications, Institute of Electrical Engineers of Japan (18.11.1985) 1–24 (1985)

  41. M. Borissov, L. Spassov, E. Yosifov, D. Mikhailov, E. Radeva, R. Zakharieva, High-Frequency Thermosensitive Quartz Resonators, Bulgarian Journal of Physics, 11 (6) 603–610 (1984)

  42. M. Borissov, D. Dechev, E. Yossifov, V. Kusev, L. Spassov, Studies of the hydrothermal growth of piezoelectric quartz, Bulgarian Journal of Physics, 9 (4) 353–366 (1982)

  43. M. Borissov, D. Dechev, E. Yossifov, L. Spassov, I. Batandjiev, Growth of piezoelectric quartz crystals of a new type of raw material, Comptes rendus de l’Academie bulgare des Sciences, 35 (6) 761–763 (1982)

  44. M. Borissov, M. Velchev, K. Gruncharov, D. Dechev, E. Yosifov, L. Spassov, A Pilot precision autoclave for hydrothermal growth of quartz crystals, Bulgarian Journal of Physics, 8 (6) 614–624 (1981)

  45. K. Grantcharov, M. Borissov, D. Detchev, L. Spassov, E. Yossifov, Investigations on a new force-frequency measuring gauge, Electronics letters, 16 (2) 71–72 (1980)

  46. L. Spassov, M. Borissov, Studies on monolithic quartz filters, Bulgarian Journal of Physics, 4, (5) 523–532 (1977)

  47. M. Onoe, L. Spassov, An experiment of two dimensional monolithic crystal filters, U Tokio Repozitory, Institute of Industrial Science, University of Tokyo, Volume 25, No. 12, p. 549-551 (1973)

  48. L. Spassov, M. Borissov, Bulgarian Journal of Physics 4, (1971), 5

Izpolzvana literatura

  1. A. G. Petrov, Jubilee collection 30 Anniversary of the Institute of Solid State Physics, Bulgarian Academy of Sciences 1972-2002, Sofia (2002) 208-225

  2. Ë. Ñïàñîâ, Ã. Êàìèøåâà, Ìèëêî Áîðèñîâ çà ñåáå ñè è äðóãèòå çà íåãî (1921–1998), ÀÈ Ìàðèí Äðèíîâ, Ñîôèÿ (2008) c. 226

Protocol for Adoption 1
 (20 March 2003)

  1. Foto with Milko Borissov from Gjuletchitsa (1983)

Back