Petkov, Valeri

• V. Petkov, R. Baumbach, AM Milinda Abeykoon and J. A. Mydosh "3D charge density wave in the dual fermion system UPt2Si2" Phys. Rev. B 107, 245101 (2023). 
  
• V. Petkov, A. Zafar, P. Kenesei and S. Shastri "Chemical compression and ferroic orders in La substituted BiFeO3" Phys. Rev. Mat. 7, 054404 (2023). 
  
• Valeri Petkov, Adeel Zafar, Durga R Tadisetti1, and M. AM Abeykoon "Lattice instability and magnetic phase transitions in strongly correlated MnAs" J. Phys.: Condens Matter 35, 315401 (2023). 
  
•  Jorge R. Galeano-Cabral, Eliana Karr, Benny Schundelmier, Olatunde Oladehin, Eun S. Choi,Theo Siegrist, Juan Ordonez, Sarvjit Shastri, Valeri Petkov, Ryan E. Baumbach, and Kaya Wei "Enhanced thermoelectric properties of heavy-fermion compounds YbxCeySmzIr2Zn20 (x + y + z = 1)" Phys. Rev. Mat. 7, 025406 (2023). 
  
•  Ezgi Yildirim, Raj Kumar Ramamoorthy, Rohan Parmar, Pierre Roblin, Jorge A. Vargas, Valeri Petkov, Ana Diaz, Stefano Checchia, Isaac Rodriguez Ruiz, Sébastien Teychené, Lise-Marie Lacroix, and Guillaume Viau "Simple Synthesis of Monodisperse Ultrasmall Au Icosahedral Nanoparticles" J. Phys. Chem. C 127, 3047 (2023).
  
• V Petkov, T Durga Rao, , A Zafar, A M Milinda Abeykoon, E Fletcher, J Peng, Z Q Mao and X Ke” Lattice distortions and the metal–insulator transition in pure and Ti-substituted Ca₃Ru₂O₇” J. Phys.: Condens. Matter 51, 015402 (2023). 
• V. Petkov, T. D. Rao, AM Milinda Abeykoon, Jorge R. Galeano-Cabral, and K.Wei “Spin-lattice coupling in magnetocaloric Gd₅(Ge,Si)₄ alloys by in-situ x-ray pair distribution analysis in magnetic field”. Phys. Rev. Mater. 6, 104407 (2022).  
• V. Petkov, J. E. Peralta, B. Aoun and Y. Ren “;Atomic structure and Mott nature of the insulating charge density wave phase of 1T-TaS₂”  J. Phys.: Condens. Matter 34, 345401 (2022). 
• L. Ma, J. Vatamanu, N. T. Hahn, T. P. Pollard , O. Borodina, V. Petkov, M. A. Schroeder, Y. Ren, M. S. Ding, C. Luo, J. L. Allen , C. Wang, and K. Xua   “Highly reversible Zn metal anode enabled by sustainable hydroxyl chemistry” PNAS 119, e2121138119 (2022).                                 
• H. Kareem, Y. Maswadeh, Zhi-Peng Wu, A. C. Leff, Han-Wen Cheng, S. Shan, S. Wang, R. Robinson, D. Caracciolo, A. Langrock, D. M. Mackie, D. T. Tran, V. Petkov, and C.-J. Zhong “Lattice Strain and Surface Activity of Ternary Nanoalloys under the Propane Oxidation Condition” ACS Appl. Mat. & Interfaces 14, 11435 (2022).  
  

• Ph.D., Physics, University of Sofia, Bulgaria, 1991
• M.S., Physics, University of Sofia, Bulgaria, 1983

• Applied crystallography
• X-ray (synchrotron) diffraction
• 3-D structure determination and modeling
• Magnetism
  

Research projects

• Properties of materials are predetermined by the atomic-scale structure. For example, diamonds are hard, transparent and expensive. Graphite is black, soft and cheap. Both are pure carbon though; the difference comes from the different arrangement of carbon atoms. It is a tetrahedral network in diamond and a stack of hexagonal layers in graphite. Dr. Petkov's research aims at determining the 3D atomic-scale structure of materials by x-ray diffraction and computer simulations. Research is done at CMU and synchrotron radiation facilities. Mostly, a non-traditional experimental approach, that of atomic pair distribution function analysis, is employed. Traditional crystallography (Rietveld) is done as well. Materials of current interest include glasses (metallic, silicate, phosphate, germanate, fast conductors), liquids (water), polymers (dendrimers), composites (inorganic/organic), nanoporous zeolites and carbons, ceramics (titanates, zirconates), catalysts (Mo, Au and Pt based), nanoparticles (metallic and inorganic), data storage media (optical: Ge-Sb-Te; magnetic: Pt/Pd/Fe), disordered ferro and ferri magnets (transition & rare earth metals based), and others. Funding sources include NSF, DoE, ARL and CMU.​