Mohamad M. AHMAD
 Contract Researcher		  

June 1994 Bachelor of Science, Assiut University,Egypt
September 1999 Master of Science, Faculty of Science, Assiut University,Egypt
February 2004 Ph.D., (Experimental Solid State Physics)Faculty of Science, Assiut University,Egypt
Doctor thesis "Ion Dynamics and relaxation in Fluoride Ion Conductors PbSnF4, KSn2F5 and RbSn2F5 Studied by NMR and Impedance Spectroscopy"


1995-1999 Instructor of Physics, Faculty of Education in The New Valley, Assiut University,Egypt
1999-2001 Assistant Lecturer, Faculty of Education in The New Valley, Assiut University,Egypt
2001-2003 Guest Researcher, Graduate School of Science, Hiroshima University,Japan
2004-2006 Lecturer of Physics, Faculty of Education in The New Valley, Assiut University,Egypt
2006-2008 JSPS Postdoctoral Fellow, Nihon University,Japan
2008 to 2009 Contract Researcher, Condensed Molecular Materials Group,Japan


         ・Dielectric properties of Molecular Conductors
         ・Ionic conduction and relaxation in fluoride and alkali ion conductors.
         ・Dielectric relaxation properties of inorganic solids.

  1. M.A. Hefni, M.A. Osman, R.M. Mahfouz and M.M. Ahmad
    "Electron paramagnetic resonance studies of -ray irradiated Li2SO4- K2SO4 mixed crystals"
    Arab J. Nucl. Sci. Appl. 32, 190 (1999).

  2. M.A. Hefni, M.A. Osman, R.M. Mahfouz and M.M. Ahmad
    "Electron paramagnetic resonance, infrared, and electrical conductivity studies of -ray irradiated Li2SO4- K2SO4 mixed system"
    Radiat. Eff. Def. Solids, 152, 255 (2000)

  3. M.A. Osman, M.A. Hefni, R.M. Mahfouz and M.M. Ahmad
    "Spectroscopic studies and electrical conductivity behavior of -irradiated Li2SO4- Na2SO4 mixed system"
    Radiat. Eff. Def. Solids 153, 115 (2001)

  4. M.A. Hefni*, M.A. Osman, R.M. Mahfouz and M.M. Ahmad
    "γ-irradiation effect on the spectroscopic and electrical properties of K2SO4-Na2SO4 mixed system"
    Radiat. Eff. Def. Solids 153, 151 (2001).

  5. M.M. Ahmad and M.A. Hefni
    "DSC and electrical conductivity studies of (Li1-xKx)2SO4 mixed crystals"
    Radiat. Eff. Def. Solids 153, 359 (2001)

  6. M.A. Osman, M.A. Hefni, R.M. Mahfouz and M.M. Ahmad
    "γ-irradiation effect on the electrical properties of LiKSO4"
    Physica B, 301, 318 (2001)

  7. M.M. Ahmad and M.A. Hefni
    "Effect of Li content on the DSC and electrical conductivity of (Li1-xKx)2SO4 mixed crystals"
    Zeitschrift fur Naturforschung A 56, 677 (2001)

  8. M.M. Ahmad, K. Yamada and T. Okuda
    "Frequency dependent conductivity and dielectric studies on RbSn2F5"
    Solid State Commun. 123, 185 (2002).

  9. M.M. Ahmad, K. Yamada and T. Okuda
    "Fluoride ion diffusion of superionic PbSnF4 studied by NMR and impedance spectroscopy"
    J. Phys.: Condens. Mat. 14, 7233 (2002)

  10. M.M. Ahmad, M.A. Hefni, A.H. Moharram, G.M. Shurit, K. Yamada and T. Okuda
    "Fluoride ion dynamics and relaxation in KSn2F5 studied by 19F NMR and impedance spectroscopy"
    J. Phys.: Condens. Mat. 15, 5341 (2003).

  11. M.M. Ahmad, K. Yamada and T. Okuda
    "Ionic conduction and relaxation in KSn2F5 fluoride ion conductor"
    Physica B 339, 94 (2003)

  12. K. Yamada, M.M. Ahmad, H. Ohki, T. Okuda, H. Ehrenberg and H. Fuess
    "Structural phase transition of the two-dimensional fluoride ion conductor KSn2F5 studied by X-ray diffraction"
    Solid State Ionics 167, 301 (2004).

  13. M.M. Ahmad, K. Yamada and T. Okuda
    "Conductivity spectra and comparative scaling studies of polycrystalline PbSnF4"
    Solid State Ionics 167, 285 (2004).

  14. K. Yamada, M.M. Ahmad, Y. Ogiso, T. Okuda, J. Chikami, G. Miehe, H. Ehrenberg and H. Fuess
    "Two dimensional fluoride ion conductor RbSn2F5 studied by impedance spectroscopy and 19F, 119Sn and 87Rb NMR"
    Eur. Phys. J. B 40, 167 (2004)

  15. Mohamad M Ahmad
    (Invited paper) "Ionic conduction and relaxation in some superionic fluoride ion conductors", in "Defects and Diffusion in Halides and Ice - A 7-Year Retrospective"
    David J. Fisher (Trans Tech Publications Inc., Switzerland), pp. 1-27, September, (2004).

  16. Mohamad M Ahmad
    "Estimation of the charge-carrier concentration and ac-conductivity scaling properties near the V-I phase transition of polycrystalline Na2SO4"
    Phys. Rev. B 72, 174303 (2005).

  17. M.M. Ahmad, E. Yousef and E. Mostfa
    "Dielectric properties of the ternary TeO2-Nb2O5-ZnO glasses"
    Physica B 371, 74 (2006).

  18. Mohamad M Ahmad
    "Ionic conduction and dielectric relaxation in polycrystalline Na2SO4"
    Solid State Ionics 177, 21 (2006).

  19. M.M. Ahmad, S.A. Makhlouf and K.M.S. Khalil
    "Dielectric behavior and ac conductivity of NiO/Al2O3 nanocomposites in humid atmosphere"
    J. Appl. Phys. 100, 094323 (2006).

  20. J.R. Macdonald and M.M. Ahmad
    "Slopes, nearly constant loss, universality, and hopping rates for dispersive ionic conduction"
    J. Phys.: Condens. Mat. 19, 046215 (2007).

  21. M.M. Ahmad, M.A. Gaffar, K. Yamada and T. Okuda
    "Ion dynamics and structure-dependent conductivity scaling properties in polycrystalline LiK1-xRbxSO4"
    J. Phys. Chem. Solids 68, 470 (2007).

  22. M.M. Ahmad, K. Yamada, P. Meuffels and R. Waser
    "Aging-induced dielectric relaxation in barium titanate ceramics"
    Appl. Phys. Lett. 90, 112902 (2007).

  23. M.A. Gaffar, M.M. Ahmad, K. Yamada and T. Okuda
    "The double-peak phenomenon of the phase transition of Rb substituting K in LiKSO4, competition between Rb sub-lattice and smearing the phase transition"
    J. Phys. D: Appl. Phys. 40, 4360 (2007).

  24. M.M. Ahmad and K. Yamada
    "Superionic PbSnF4: A giant dielectric constant material"
    Appl. Phys. Lett. 91, 052912 (2007).

  25. M.M. Ahmad, Y. Yamane, K. Yamada and S. Tanaka
    "Dielectric relaxation properties of Pb1-xSnxF2 solid solutions prepared by mechanochemical milling"
    J. Phys. D: Appl. Phys. 40, 6020 (2007).

  26. M.M. Ahmad and K. Yamada
    "Hopping rates and concentration of mobile fluoride ions in Pb1-xSnxF2 solid solutions"
    J. Chem. Phys. 127, 124507 (2007).


  1. The 1st Egypt - Japan International Symposium on Science and Technology, 8 - 10 June 2008,
           Waseda University, Tokyo, Japan.
           M.M. Ahmad and K. Yamada
          "Ion dynamics and giant dielectric constant in Pb1-xSnxF2 solid solutions"

  2. The 2nd International Conference on Physics of Solid State Ionics, 16 - 19 December 2007,
          Tokyo Institute of Technology, Yokohama, Japan.
          M.M. Ahmad and K. Yamada
          "Ionic conduction and relaxation properties in mechanochemically synthesized BaSnF4"

  3. The 1st International Conference on Materials Science & Technology (Future Challenges), 2 - 4 December 2007,
          National Research Center, Cairo, Egypt.
          M.M. Ahmad and K. Yamada
          "Ion dynamics and giant dielectric properties in nanocrystalline Pb1-xSnxF2 solid solutions"

  4. The 87th Spring Meeting of the Chemical Society of Japan, 25 - 28 March 2007,
          Kansai University, Osaka, Japan.
          M.M. Ahmad, Y. Yamane and K. Yamada
          "Ionic conduction and relaxation phenomena in solid solutions between lead fluoride and tin fluoride"

  5. The 87th Spring Meeting of the Chemical Society of Japan, 25 - 28 March 2007,
          Kansai University, Osaka, Japan.
          K. Yamada*, H. Suzuki, M.M. Ahmad and Y. Yamane
          "Lithium ion conductivity of halide spinel"

  6. The 32nd Symposium on Solid State Ionics, 27 - 29 Nov. 2006,
          Kyushu University, Kyushu, Japan.
          K. Yamada*, H. Suzuki, M.M. Ahmad and Y. Yamane
          "Lithium ion conductivity for spinel halides "


  1. M.M. Ahmad　
    "Conductivity and dielectric relaxations in ionically conducing crystals"
    in 'Focus on Condensed Matter Physics Research',edited by John V. Chang(Nova Science Publishers,Inc.,New York),Chapter3,(2005).


  1. 1- The Egypt State Award of Physical Sciences 2007.
    Awarded by the Academy of Scientific Research and Technology, Egypt.


  2. 2- JSPS postdoctoral fellowship 2006-2008 at Nihon University, Japan.
    Awarded by the Japan Society for the Promotion of Science.


  3. 3- Guest Researcher 2001-2003 at Hiroshima University, Japan.
    A scholarship awarded by the Ministry of Higher Education, Egypt.





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