Abou me

My name is Hossein Khosroabadi. I was born in Sep. 20, 1977 in Sabzevar city of Iran, and grow up in Tehran.  I graduated in Bachelor of Science in Solid Satet Physics from Mazandaran University by Sep 1998. I have done my Master and PhD thesis in the filed of High Temperature Superconductivity (HTSC) under the supervision of Prof. M. Akhavan at Sharif University of Technology (Tehran, Iran) by 2000 and 2006, respectively. My research was concentrated on transport measurements and ab-initio density functional theory calculations of YBCO family of HTSCs.  I have passed the JSPS postdoctoral in Osaka University by investigating the phonon properties of Ba1-xKxBiO3 system by Inelastic X-ray Scattering experiments.  Now, I am postdoctoral researcher at the Institute of multidisciplinary research for advanced material (IMRAM) of  Tohoku University (Sendai, Japan). My research subject is “Radiation and thermophysical properties of molten metals and semiconductors”.     

My hobbies are hiking, chess, cooking and watching movies.

Some parts of my CV and the abstract of my studies are presented in the following:

Awards and Honors

  • Japan Science and Technology (JST) postdoctoral fellowship for two years, Tohoku University, Sendai, Japan (2008). 
  • Iran Physical Society Award for Excellent Research PhD study in Iran (2006).
  • Japan Society for the Promotion of Science (JSPS) postdoctoral fellowship for two years, Osaka Univ., Japan (2006).
  • International Junior Associate program, International center for theoretical Physics, Italy (2005).
  • Distinguished National Ph.D. Student in Basic Science of Iran (2004).
  • Iran National Khwarizmi Young Festival, 1st place Award (2002).
  • Iran Physical Society Award for Best Achievement in Research (2001).

Publications

1. H. Khosroabadi, B. Mossalla, and M. Akhavan, Phys. Rev. B 76 (2007) 54508 [selected by the Virtual Journal of Applications of Superconductivity, Aug. 15, 2007].

2. H. Khosroabadi, B. Mossalla, and M. Akhavan, Phys. Stat. Sol. 3 (2006) 3140. 

3. H. Khosroabadi, A. Tavana, and M. Akhavan, Eu. J. Phys. B 51 (2006) 161.

4. H. Khosroabadi, A. Tavana, B. Mossalla, and M. Akhavan, Iran. J. Phys. Res., Special Issue of Two Decades of HTSC, 6 (2006) 187.

5. A. Tavana, H. Khosroabadi, and M. Akhavan, Phys. Stat. Sol. 3 (2006) 3162.

6.  H. Khosroabadi, and M. Akhavan, J. of Superconductivity 18 (2005) 269.

7. H. Khosroabadi, B. Mossalla, and M. Akhavan, Phys. Rev. B 70 (2004) 134509 [selected by the Virtual Journal of Applications of Superconductivity, Nov. 1, 2004].

8. H. Khosroabadi, M. Modarreszadeh, P. Taheri, and M. Akhavan, J. of Superconductivity 17 (2004) 749.

9. H. Khosroabadi and M. Akhavan, Phys. Stat. Sol. (c) 1 (2004) 1863.

10. H. Khosroabadi, B. Mossalla, and M. Akhavan, Phys. Stat. Sol. (c) 1 (2004) 1859. 

11. H. Khosroabadi, M. Modarreszadeh, P. Taheri, and M. Akhavan, Phys. Stat. Sol. (c) 1 (2004) 1867. 

12. H. Khosroabadi, V. Daadmehr, and M. Akhavan, Physica C 384 (2003) 169.

13. H. Khosroabadi, M.R. Mohammadizadeh, and M. Akhavan, Physica B 321 (2002) 360.

14. H. Khosroabadi, M.R. Mohammadizadeh, and M. Akhavan, Physica C 370 (2002) 85.

15. H. Khosroabadi, V. Daadmehr, and M. Akhavan, Mod. Phys. Lett. B 16 (2002) 943.

16. H. Khosroabadi, M.R. Mohammadizadeh, and M. Akhavan, Iran. J. Phys. Res. 3 (2002) 59.

17. H. Khosroabadi, V. Daadmehr, and M. Akhavan, Iran. J. Phys. Res. 3 (2002) 153.

18. M.R. Mohammadizadeh, H. Khosroabadi, and M. Akhavan, Physica B 321 (2002) 301. 

19. M. Maleki, H. Khosroabadi and M. Akhavan, Phys. Stat. Sol. (c) 1 (2004) 1871.

20. M. Mirzadeh, H. Khosroabadi and M. Akhavan, Phys. Stat. Sol. (c) 1 (2004) 1875.

21. M. Kariminezhad, H. Khosroabadi and M. Akhavan, Phys. Stat. Sol. (c) 1 (2004) 1855.

22. Z. Mokhtari, H. Khosroabadi and M. Akhavan, Phys. Stat. Sol. (c) 1 (2004) 1891.

23. M.R. Mohammadizadeh, H. Khosroabadi, H. Akbarzadeh, and M. Akhavan, in: Proceedings of the First Regional Conference on Magnetic and Superconducting Materials (MSM-99), eds. M. Akhavan, J.Jensen, and K. Kitazawa, (World Scientific, Singapore, 2000) p. 251.

   Previous Research

In my MSc and PhD thesis I have been a member of groups working on different properties of high-Tc superconductors (HTSC) from the experimental and computational point of views. Here I summaries the most significant results we have obtained in these studies:

     In the experimental studies we have prepared a variety of Y123 compounds with different doping, then characterization and electrical and magnetic transport properties of the samples have been investigated.

1) Some interesting scaling relations of vortex pining energy vs. magnetic filed, temperature and superconducting transition width have been found as U~H(1-T/Tc)q (with β≈1/3 and q≈2-3), ∆Tc~Hn and U~∆TcH for GdPr123 system.

2) By investigating the simultaneous effects of oxygen deficiencies and Pr doping, the suppression of superconductivity by Pr doping in GdPr123 has been explained as a combination of localization and hole filling of the carriers in the CuO2 planes.

3) By studying the mixing granular samples, it has been found that suppression of superconductivity in (1-m)Gd123-mPrBa123 is considerably weaker than (1-n)Gd123-nPr123, which seems to be useful for application point of views of mixed granular samples.

4) It has been concluded that observation of superconductivity is possible for Ba-rich Pr123, and Pr123 system with correct stoichiometry is an insulator. This is resulted from studying the Pr/Ba mis-substitution in Pr123,

5) By studying the effect of light and heavy rare earth ions and Sr and Ca cation substitutions, it has been concluded that the ionic size of rare earth elements is essential in the mechanism of suppression of superconductivity by Pr doping in these systems, and the critical concentration of Pr is increased in heavy rare earth compounds.  

      In the computational studies we have calculated the electronic band structure, mechanical high pressure, chemical pressure, charge transfer, phonon frequencies and electron-phonon interaction of Y123, Y124, YSCO, Gd123 and Pr123 by ab-initio simulation based on density functional theory.

1) It has been shown that the psedupotetntial method has enough accuracy to calculate the electronic structure, lattice structure, physical properties, and phonon properties of HTSC compounds.

2) It has been founded that the apical oxygen position in Y123 system is important in the hole concentration of CuO2 planes, and could be considered to optimize the Tc of these systems.

3) Mechanical pressures could effect the superconducting properties by changing the hole concentration in the CuO2 planes, confirm the charge transfer model.

4) The opposite behavior of the mechanical and chemical pressure on Tc has been explained on the contraction of CuO2-Y-CuO2 blocks under these two pressures.

5) The eigenvalues and eigenvectors of Raman Ag modes of Gd123, Y123, Y124, and Pr123 are in reasonably agreement with the experimental and other computational data.

6) The strong ionic position dependence of electronic band structure of Y123 and Y124 compounds has been interpreted as a potentially strong electron-phonon interaction in HTSC compounds. 

Present research

Recent experiments have confirmed the existence of phonon softening in some of HTSCs and other superconductors (MgB2 and BKBO), which seems to be a good clue to understanding the role of electron-phonon interaction in the mechanism of superconductivity in these systems. Now, we are studying the phonon softening of Ba1-xKxBiO3 (BKBO) system.

Since only small crystals are available in the low content of potassium, we have applied Inelastic X-ray Scattering (IXS) measurement rather than neutron scattering for these measurements.

Single crystals of BKBO system (different doping value) have been grown by the electrochemical method. These samples have been characterized by the powder and Laue X-ray diffraction and SQUID magnetometry to check the crystal and superconducting properties. The phonon properties of this system have been calculated by dynamical shell model to obtain some theoretical understanding and necessary information for doing IXS measurement. The phonon spectrums of these samples have been measured by the method at the beam line 35 of super photo ring facilities (SPring-8) in Japan. From the analysis of IXS spectra we have been able to determine the acoustic and optical phonon branch for the system. Now, we are continuing our measurements to derive a conclusive result for this system. 

 

Updated: October 20,2007

 

 Sendai, August 2007

6 Comments

  1. 1
    taha Says:

    I hope to be successful

  2. 2
    mojtaba Says:

    Hi dear Dr. Khosroabadi
    I was one of students in your graduate superconduntivity course in sharif university, I am glad to see your web, it was so long time that i had not any news about you!
    I want to ask you aobut phonon softening, please introduce me a good source for this topic.
    i had found many answers of my questions in your class, I hope to meet you again,
    best regards
    Mojtaba Mazaheri

  3. 3
    superconductivity Says:

    Hi Dear Mojtaba,
    Nice to hear from you.
    Phonon softening means the reduce of phonon ferequency by any physical parameters such as doping, temperature, phonon wave-vector Q, etc.
    It could give some information about the phonon modes interactions with other quasiparticles, or collective modes in crystal.
    There are many papers (just search with Phonon softening in APS), maybe you can find a Rev. paper. You can also see my weblog (post-4, Reznik et al. Nature 2006) to find an important and recent study in this filed.
    Hossein

  4. 4
    zahra Says:

    Dear Dr.Khosroabadi
    hi,
    I remember ,in my first friendly appointment with Dr.Akhavan he said me about a unique student,researcher,and a hardworking person he have had.It was you,a great motivation in my mind.
    I need your help,actually.I want to start my work,of course it is late,but
    I want to do my work as well as possible.In fact I have really so much waste time in my life,but I want to redress it.So,for me, It is really necessary to find how can I go my way,strongly,qualitatively,and soon.
    please help me and give me a comprehensive program about how can I start,what should I do and everything that a beginner in research needs to know and learn to be a perfect researcher and a creative physicist and an effective person in science,like you.I am going to start my reaserch in your field under Dr.Akhavan supervision.I know that I come to correctly.
    some days ago,I study in Gerard t’Hooft homepage about how to be a good theorist in physics.It is the scientisists job to learn the enthusiastic people,and now it is your turn.Please amplify my motivation by your kind to me.I will be really honored to learn from you and if you accept me as your student.

    Best Regards
    Z.Hooshmand

  5. 5
    zahra Says:

    reading your weblog is the best source of motivation!

  6. 6
    zahra Says:

    I hope you receive my emails.I sent them to your yahoo mail.
    thanks for your attention Dear Dr.Khosroabadi,really appreciate you.


RSS Feed for this entry

Leave a Comment