Scattering and excitation phenomena in an interacting electron system  Page description

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Details of project

  
Identifier
49571
Type K
Principal investigator Nagy, István
Title in Hungarian Szórási és gerjesztési jelenségek kölcsönható elektronrendszerben
Title in English Scattering and excitation phenomena in an interacting electron system
Panel Physics 1
Department or equivalent Department of Theoretical Physics (Budapest University of Technology and Economics)
Participants Apagyi, Barnabás
Starting date 2005-01-01
Closing date 2009-06-30
Funding (in million HUF) 5.070
FTE (full time equivalent) 2.51
state closed project





 

Final report

  
Results in Hungarian
A T049571 azonosítójú, "Szórási és gerjesztési jelenségek kölcsönható elektronrendszerben" című OTKA kutatási pályázatban 21 publikáció született, közte 10 Physical Review és 2 New Journal of Physics. A teljes listát a közleményjegyzék tartalmazza. Kiemelkedően fontos eredményeknek (1-2) a következőeket tartom. 1. Az ún. two-level system tématerületen meghatároztuk az elmozduló hidrogén atom és vezetési elektronok csatolását. Megmutattuk, hogy ez a csatolás a fázistolások korlátos függvénye. Igy a fizikai modell, ellentétben a korábbi perturbatív becslésekkel, nem eredményezheti az ún. two-channel Kondo effektust. 2. Az eletron-párkorreláció tématerületen meghatároztuk az ún. precursor-pairing hőmérsékletet, a Cooper-csatorna kétrészecskés Bethe-Salpeter egyenletének megoldásával. Ez az elméleti eredmény fontos lehet az új szupravezető anyagok teljes elméletének megértésében.
Results in English
During the period of the T049571 project with title "Scattering and excitation phenomena in interacting electron gases", 21 articles have been published. Among them, 10 in the Physical Review, and 2 in the New Journal of Physics. The full list of publications forms a separate part of this closing-summary. The following items (1-2) below are considered as the most important ones of the results obtained with the project-number T049571. 1. In the field of the so-called two-level system, we explicitly determined the coupling constant between a movable hydrogen atom and the conduction electrons. It is found that the coupling is a bounded function of the scattering phase shifts, contrary to earlier claims, which were based simply on estimations. Thus, one cannot realize the so-called two-channel Kondo effect with embedded (movable) hydrogen. 2. In the hot-topic field of electron pair-correlation we determined quantitatively the so-called precursor-pairing temperature. This is a key quantity to the full theoretical understanding of new, cuprate and pnictide superconductors. We solved the two-particle Bethe-Salpeter equation in the Cooper-channel with a physically constrained input (renormalized) electron-electron interaction.
Full text https://www.otka-palyazat.hu/download.php?type=zarobeszamolo&projektid=49571
Decision
Yes





 

List of publications

  
R. Vincent, J.I. Juaristi, and I. Nagy: Transport cross sections based on a screened interaction potential: Comparison of classical and quantum-mechanical results, Physical Review A 71, 062902, 2005
N.H. March, I.A. Howard, I. Nagy, and P.M. Echenique: Changes in non-linear potential scattering theory in electron gases brought about by reducing dimensionality, Journal of Mathematical Physics 46, 072104, 2005
R. Díez Muino, I. Nagy, and P.M. Echenique: Calculation of pair-correlations in a shigh-density electron gas: Constraints for effective interparticle potentials, Physical Review B 72, 075117, 2005
A. Galindo, I. Nagy, R. Díez Muino, and P.M. Echenique: Curvature of the total electron density at critical coupling, Physical Review B 72, 125113, 2005
B. Apagyi and D. Schumayer: Assessment of interspecies scattering lengths a_12 from stability of two-component Bose-Einstein condensates, Europhysics Journal B 45, 55, 2005
R. Vincent and I. Nagy: Stopping power of a degenerate electron gas for slow ions, Physical Review B 74, 073302, 2006
I. Nagy, M. Puska, and N. Zabata: Numerical study of bound states for point charges shielded by the response of a homogeneous two-dimensional electron gas, Physical Review B 74, 115411, 2006
A. Galindo, I. Nagy, R. Diez-Muino, and P.M. Echenique: Curvature of the total electron density at critical coupling. Attractive impurity in on electron gas., New Journal of Physics 8, 299, 2006
I. Nagy, N.H. March, and P.M. Echenique: Homogeneour Fermi liquid with artificial repulsive inverse square law interparticle potential energy, Physics and Chemistry of Liquids 44, 571, 2006
R. Vincent and I. Nagy,: Stopping power of a degenerate electron gas for slow ions: Role of relative kinematics in Z_1-oscillation below the Fermi velocity, Nuclear Instruments and Methods B 256, 182, 2007
R. Vincent, J.I. Juaristi, and I. Nagy,: Z_1 oscillation in spin polarization of electrons excited by slow ions in a spin-polarized electron gas, Nuclear Instruments and Methods B 258, 79, 2007
M. Quijada, A.G. Borisov, I. Nagy, R.D. Muino, and P.M. Echenique: Time-dependent density-functional calculation of the stopping power for protons and antiprotons in metals, Physical Review A 75, 042902, 2007
I. Nagy, M.J. Puska, and N. Zabala: Electron-electron interaction in two dimensional electron gas: Bound states at low densities, Physical Review B 75, 233105, 2007
R. Vincent, I. Nagy, and E. Zaremba: Strength of dipolar backflow patterns around slow protons in three- and two-dimensional electron gases, Physical Review B 76, 073301, 2007
R. Vincent, A. Lodder, I. Nagy, and P.M. Echenique: Description of a migrating proton embedded in an electron gas, Journal of Physics: Condensed Matter 20, 285218 (2008), 2008
I. Nagy, R. Vincent, J.I. Juaristi, and P.M. Echenique: Energy loss straggling of swift heavy ions in an electron gas, Physical Review A 78, 012902 (2008), 2008
N.H. March, I. Nagy, and P.M. Echenique: Neutron and X-ray diffraction from liquid Rb, Physics and Chemistry of Liquids 46, 481, 2008
I. Nagy and A. Zawadowski: Coupling of conduction electrons to two-level systems formed by hydrogen: A scattering approach, Journal of Physics: Condensed Matter 21, 175701, 2009
I. Nagy, N. Zabala, and P.M. Echenique: A model for pairing in two dimensional electron gases, New Journal of Physics 11, 063012, 2009
J. Pipek and I. Nagy: Measures of spatial entanglement in a two-electron model atom, Physical Review A 79, 052501, 2009
I. Nagy, M.L. Glasser, and N.H. March: Critically shielded potential in a three-dimensional electron gas: The induced charge density at the origin, Physics Letters A [available online at DOI: 10.1016/j.physleta.2009.06.051], 2009



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