Alexandru
Popa
received the Physicist Engineer degree from the Polytechnic
University of Bucharest, Romania in 1966, the M. Sc degree from
the University of California, Berkeley in 1972 and the Ph. D.
degree from the Polytechnic University of Bucharest, Romania in
1974. He is currently a Senior Researcher at the Laser
Department, National Institute for Laser, Plasma and Radiation
Physics, Bucharest.
Until
1975 he worked on electronic device modeling, his results being
published in IEEE Transactions on Electron Devices. During
19751989 he worked in the field of scanning electron microscopy
and X ray spectrometry, with application to the study and the
characterization of the materials. A constant research interest
was modeling optimization at the atomic and molecular scale.
In
the last period he worked in the following research fields:
In the field of connections between quantum and classical equations with applications to the modeling of stationary states he has the following achievements:
1) A wave model for stationary atomic and molecular systems [1][5].
2) A semiclassical central field method for the calculation of energetic values for stationary systems, on the basis of the previous wave model. His approach is in good agreement with experimental values, for numerous atoms and diatomic molecules. The accuracy of his method is comparable with the accuracy of the HartreeFock method [6][8].
In the field of interactions between medium and very intense laser beams and electrons, atoms and material surfaces he has the following achievements:
1) A model for metallic surfaces emitting second harmonic generator [9].
2) A nonlinear model of interaction between electromagnetic waves and polar semiconductors [10].
3) Proofs of an accurate connection between quantum and classical equations in interactions between very intense laser fields and electrons or atoms [11], [12].
4) A model of hard X radiations generation by relativistic Thomson scattering [13], [14] and a periodicity property of relativistic Thomson scattering, with application to exact calculation of angular and spectral distributions of scattered field [15].
5) A model for the study of the polarization effects in collisions between very intense laser beams and relativistic electrons [16].
6) A model for the calculation of the harmonic spectrum generated at the interaction between very intense laser fields and atoms [17].
7) A model for the calculation of the angular and spectral distributions of the radiations generated at the interaction between very intense laser beams and electron plasmas [18].
8) A calculation method for the radiation damping parameters in the interaction between very intense laser beams and relativistic electron beams [19].
A synthesis of his results is published in two books [20], [21].
SELECTED
PAPERS
A.
Popa,
"Applications
of a Property of the Schrödinger Equation to the Modeling of
Conservative Discrete Systems,"
Journal
of the Physical Society of Japan,
Vol. 67, No. 8, 1998, p. 26452652.
A.
Popa,
"Applications
of a Property of the Schrödinger Equation to the Modeling of
Conservative Discrete Systems. II,"
Journal
of the Physical
Society
of Japan,
Vol. 68, No. 3, 1999, p. 763770.
A.
Popa,
"Applications
of a Property of the Schrödinger Equation to the Modeling of
Conservative Discrete Systems. III,"
Journal
of the Physical
Society
of Japan,
Vol. 68, No. 9, 1999, p. 29232933.
A.
Popa,
“Connection
between the periodic solutions of the HamiltonJacobi equation
and the wave properties of the conservative bound systems”,
Journal
of Physics A: Mathematical and General,
Vol. 36. pp. 75697578, 2003.
A.
Popa,
“Wave
model for conservative bound systems”,
Journal
of Chemical Physics,
Vol. 122, pp 244701(16), 2005.
A.
Popa, “Semiclassical
method for calculating the energetic values of helium, lithium
and beryllium atoms,
“ European
Physical Journal D,
Vol. 49, pp. 279292, 2008.
A.
Popa, “Geometrical
symmetry of atoms with applications to semiclassical calculation
of energetic values,
“ European
Physical Journal D,
Vol. 54, pp. 575–583, 2009.
A.
Popa, “Unconventional
semiclassical method for calculating the energetic values of
diatomic molecules,”
Molecular
Physics,
Vol.
109, pp. 575–588, 2011.
A.
Popa,
M. Lazarescu, R. Dabu, A. Stratan, "A
Model of the Metallic SurfaceEmitting Second Harmonic
Generator,"
IEEE
Journal of Quantum
Electronics,
Vol. 33, No. 9, 1997, p. 14741480.
A.
Popa,
“Nonconventional
calculation of the second order susceptibility in polar
semiconductors”,
Journal
of Physics: Condensed Matter,
Vol. 15, pp. L559L564, 2003.
A.
Popa,
“A
New Approach on Studying Electron Behavior Under Very Intense
Laser Beam”,
IEEE
Journal of Quantum Electronics,
Vol. 40, pp. 15191523, 2004.
A.
Popa,
“From
Quantum to Classical Effects in Interactions Between Electrons
and Very Intense Laser Beams,”
IEEE
Journal of Quantum Electronics,
Vol. 43, pp. 11831187, 2007.
A.
Popa,
“Accurate
calculation of high harmonics generated by relativistic Thomson
scattering,
“ Journal
of Physics B : Atomic, Molecular and Optical Physics,
Vol. 41, 015601, 2008.
A.
Popa,
“Modelling
properties of hard xrays generated by the interaction between
relativistic electrons and very intense laser beams,“
Journal
of Physics B : Atomic, Molecular and Optical Physics,
Vol. 42, 025601, 2009.
A.
Popa, “Periodicity
property of relativistic Thomson scattering, with application to
exact calculation of angular and spectral distributions of
scattered field,”
Physical
Review A,
Vol. 84, 023824, 2011
A.
Popa, “Polarization effects in collisions
between very intense laser beams and relativistic electrons,”
Laser
and Particle Beams,
Vol. 30, pp. 591603, 2012.
A.
Popa, “Dependence of Harmonic Spectrum
Shape on Laser Beam Intensity in Interaction with Atoms,”
IEEE
Journal of Quantum Electronics,ol. 49, pp. 522527, 2013.
A.
Popa, “Accurate Calculation of High Harmonics
Generated by Interactions between Very Intense Laser Fields and
Electron Plasmas,”
IEEE Transactions
on Plasma Science,
Vol. 41, pp. 22462250, 2013.
A.
Popa, Accurate calculation of radiation damping parameters in the interaction between very intense laser beams and relativistic electron beams,
Laser and Particle Beams,
Vol. 32, pp. 477486, 2014.
BOOKS
A.
Popa, Theory of Quantum and Classical Connections in Modeling Atomic, Molecular and Electrodynamic Systems,
ElsevierAcademic Press, Amsterdam, Boston, 2013.
A.
Popa,
Applications of Quantum and Classical Connections in Modeling Atomic, Molecular and Electrodynamic Systems,
ElsevierAcademic Press, Amsterdam, Boston, 2013.
