Postdoc/Research Associates

Dr. Oleg P. Varnavski : Research Associate

Dr. Oleg P. Varnavski

Research Associate

 

Academic History

  • Doctor of Philosophy (Ph.D), 1984
    • P.N.Lebedev Physics Institute.
    • Thesis: "Efficient Regimes of Generation and Amplification of Ultrashort Light Pulses in Ruby and Nd :YAG ".
  • Master of Science , 1974
  • Moscow Institute of Physics and Technology (MIPT), Department of General and Applied Physics.
  • Bachelor of Science, 1972
    • Moscow Institute of Physics and Technology (MIPT), Department of General and Applied Physics.

Research Achievements

  • 1972 -1973 - Investigation of optical continuum generation by picosecond pulses.
  • 1974-1985 - Building up and study of efficient pulsed mode-locked ruby and Nd:YAG lasers. One of the first mode-locked lasers based on LiF:F2+-stabilized color centers (1980).
  • 1981-1986 - An investigation of the coherent interaction of ultrashort light pulses with resonant medium (when the pulse duration is shorter than the phase relaxation time of the resonant transition). The case of resonant transition with population inversion has been studied extensively, including such regimes as lethargic gain, coherent amplification, induced superradiance.
  • 1986-1990 - Study of the fast mobility of fluorescent probes in micellar solutions.
  • 1994 - An investigation of the electric field induced dynamics of photoexcitations in organic photoconductors.
  • 1993-1998 - Excitation dynamics in molecular aggregates and related low dimensional organic molecular systems (J-aggregates, dendrimers, etc.). Collective excitations and their relaxation were in the focus of the experimental work.
  • 1999-present - Nonlinear optical properties and femtosecond excitation dynamics of organic macromolecular systems. Excited state dynamics, relaxation processes, energy transfer dynamics

Total number of publications in referred journals: 73

Recent Publications

  • O. Varnavski, L. Sukhomlinova, R. Twieg, T. Goodson III. Ultrafast Exciton Dynamics in a Branched Molecule Investigated by Time-Resolved Fluorescence, Transient Absorption, and Three-Pulse Photon Echo Peak Shift Measurements J. Phys. Chem. B, 108 (2004) pp.10484-10492
  • T. Goodson, O. Varnavski, Y. Wang. Optical properties and applications of dendrimer-metal nanocomposites International Reviews in Physical Chemistry 23 (1) (2004) pp.109-150.
  • Sridhar Arun Lahankar, Richard West, Oleg Varnavski, Xingbin Xie, Ludmila Sukhomlinova, Robert Twieg,and T. Goodson III. Electronic interactions in a branched chromophore investigated by nonlinear optical and time-resolved spectroscopy J. Chem. Phys. 120(1) (2004) pp337-344,
  • Oleg P. Varnavski, Mona B. Mohamed, Mostafa A. El-Sayed, and Theodore Goodson III. Relative Enhancement of Ultrafast Emission in Gold Nanorods J. Phys. Chem. B 107 (2003) pp.3101-3104
  • M. I. Ranasinghe, O.P. Varnavski, J. Pawlas, S.I. Hauck, J. Louie, J.F. Hartwig, T. Goodson III. Femtosecond Excitation Energy Transport in Triarylamine Dendrimers J. Am. Chem. Soc. 124 (2002) p. 6520
  • O. Varnavski, I.D.W. Samuel, L.O. Palsson, R. Beavington, P.L. Burn, T. Goodson III. Investigation of Excitation Energy Transfer and Intramolecular Interactions in a Nitrogen Cored Distyrylbenzene Dendrimer System J. Chem. Phys ., 116 (2002) p. 8893
  • O.P. Varnavski, J.C. Ostrovski, L. Sukhomlinova, R.J. Twieg, G.C. Bazan, T. Goodson III. Coherent Effects in Energy Transport in Model Dendritic Structures Investigated by Ultrafast Fluorescence Anisotropy Spectroscopy. J. Am. Chem. Soc ., 124 (2002) p.1736
  • O. Varnavski, R. G. Ispasoiu, L. Balogh, D. Tomalia T. Goodson III. Ultra-fast Time-Resolved Photoluminescence from Novel Metal-Dendrimer Nanocomposites J. Chem. Phys. , 104 (2001) p.179
  • R.G. Ispasiou, L. Balogh, O.P. Varnavski, D.A. Tomalia, T. Goodson III. Large Optical Limitinng and Ultrafast Luminescence Dynamics from Novel Metal-Dendrimer Nanocomposite Materials J. Am. Chem. Soc., 122 (2000) p.11005.
  • O.Varnavski, G. Menkir, I. D. W. Samuel and J. M. Lupton , R. Beavington, P. Burn, and T. Goodson III, Ultra-fast Polarized Dynamics in an Organic Dendrimer, Appl. Phys. Letts ., 78 , (2000) p. 1120.
  • O. Varnavski, A. Leanov, L. Liu, J. Takacs, and T. Goodson III. Large Nonlinear Refraction and Higher Order Nonlinear Optical Effects in a Novel Organic Dendrimer J. Phys. Chem. , 104 , (2000) p.179.
  • O. Varnavski, A. Leanov, L Liu, J. Takacs, and T. Goodson III. Femto-second Photo-dynamics and Energy Transfer in an Organic Dendrimer, Phys. Rev.B , B15 , (2000) p. 114,
  • R.G. Ispasiou, M. Narawal, O. Varnavski, J. Yan, H. Pass, J. Fugaro and T. Goodson. Nonlinear Absorption and Biomedical Applications of Novel Organic Polymeric Materials, Macromolecules , 33 , (2000) p. 4061.
Sung Hei Yau : Post Doctoral Researcher

Sung Hei Yau

Post Doctoral Researcher

 

Academic History

  • Doctor of Philosophy , 2013
    • Chemistry Ph.D., Program. Physical, Chemistry
    • University of Michigan, Ann Arbor, MI
    • Thesis Title "Understanding Metal Nanoclusters Through Ultrafast and Nonlinear Spectroscopy"
  • Bachelor of Science in Chemistry, 2007
    • University of Michigan, Ann Arbor, MI

Research Interests

  • Transient absorption and ultra fast excited state dynamics of metal clusters, inculding gold and silver systems.
  • Exploratory research on new types of metal alloy nanoclusters

Recent Publications

  • Ultrafast Optical Properties of Ag32. In preparation.
  • An Ultrafast Look at Au Nanoclusters, Accounts of Chemical Research, 2013, 46 (7), 1506
  • "Ultrafast Optical Study of Small Gold Monolayer Protected Clusters: A Closer Look at Emission", J. PHY. CHEM. C, 2010,114,15979-15985
  • "Bright two-photon emission and ultra-fast relaxation dynamics in a DNA-templated nanocluster investigated by ultra-fast spectroscopy", Nanoscale, 2012, 4, 4247

Awards

  • University of Michigan Chemistry Department Winter Fellowship (2012)
  • 16th Int. Conference on Luminescence Best Paper Award (2011), physical division
  • Vaughan Symposium Travel award, sponsored by Dow Chemical (2009)
Dr. Hyungjun Kim : Post Doctoral Researcher

Dr. Hyungjun Kim

Post Doctoral Researcher

 

Academic History

  • Doctor of Philosophy , 2014
    • KAIST(Korea Advanced Institute of Science and Technology)
    • Advisor : Yoon Sup Lee
    • Thesis Title " Metal complex in solution : A theoretical investigation"
  • Bachelor of Science in Chemistry, 2008
    • KAIST(Korea Advanced Institute of Science and Technology)

Research Interests

  • Method development in electronic structure theory
  • Improved modeling of interaction in solution phase
  • Characterization of excited electronic state and electron transfer
  • Investigation of molecular design principle

Recent Publications

  • Two protocols to evaluate hydration enthalpy and reduction potential of hydrated 3d transition metal: High level ab initio calculation combined with modified CAM-B3LYP functional, In manuscript.
  • Prediction of the reduction potential of tris(2,2�-bipyridinyl)Iron(III/II) derivatives, J. Comput. Chem., 36, 33 (2015)
  • Heteroleptic cyclometalated iridium(III) complexes supported by triarylborylpicolinate ligand: Ratiometric turn-on phosphorescence response upon fluoride binding, Inorg. Chem., 53, 8672 (2014)
  • A protocol to evaluate one electron redox potential for iron complexes, J. Comput. Chem., 34, 2233 (2013)
Dr. Benedetta Carlotti : Research Associate

Dr. Benedetta Carlotti

Research Associate

Dr. Mopelola Idowu : Post Doctoral Researcher

Dr. Mopelola Idowu

Post Doctoral Researcher

 

Academic History

  • Doctor of Philosophy , 2009
    • Rhodes University, Grahamstown, South Africa
    • Thesis Title "Thesis Title: Photophysical and photochemical behavior of metallophthalocyanines: effect of nanoparticles and molecules of biological importance"
  • Master of Science in Chemistry, 1997
    • University of Ibadan, Nigeria
  • Bachelor of Science with Honours in Chemistry, 1994
    • University of Ibadan, Nigeria

Research Interests

  • Optimization, characterization and ultrafast excited state dynamics of hybrid inorganic-organic materials useful as photovoltaic devices
  • Transient studies in solar energy conversion processes
Dr. Prabhat Kumar Sahu : Research Associate

Dr. Prabhat Kumar Sahu

Research Associate