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Ermolaev, A.M.; Puzynin, I.V.; Selin, A.V.; Vinitskij, S.I.
Laboratory of Computing Techniques and Automation, Joint Institute for Nuclear Research, Dubna (Russian Federation); Bogolyubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, Dubna (Russian Federation)1999
Laboratory of Computing Techniques and Automation, Joint Institute for Nuclear Research, Dubna (Russian Federation); Bogolyubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, Dubna (Russian Federation)1999
AbstractAbstract
[en] We formulate integral boundary conditions for the time-dependent Schroedinger equation describing an atom with the laser interaction in the dipole approximation. The boundary conditions are imposed on the solution on a surface (boundary) which may be at a finite (but sufficiently remote) distance from the atom. For the numerical integration of the Schroedinger equation, these exact conditions may be used to replace diffuse absorbing potentials or mask functions. These later are usually introduced in order to (approximate) compensate unphysical reflection which occurs at the boundary of a finite region when a zero-value condition is imposed there on the solution. The method allows to substantially reduce the size of the space domain where integration is carried out numerically. Considering the numerical solution of the same one-dimensional model as that discussed by Boucke et al. (1998), we demonstrate the success of our approach
Primary Subject
Source
1999; 24 p; 28 refs., 6 figs. Submitted to Physical Review. A
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Toscano, Fabricio; Almeida, M. Ozorio de
Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil)1999
Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil)1999
AbstractAbstract
[en] We construct a semiclassical expression for the Husimi function of autonomous systems in one degree of freedom, by smoothing with a Gaussian function an expression that captures the essential features of the Wigner function in the semiclassical limit. Our approximation reveals the center and chord structure that the Husimi function inherits from the Wigner function, down to very shallow valleys, where lie the Husimi zeros. This explanation for the distribution of zeros along curves relies on the geometry of the classical torus, rather the complex analytic properties of the WKB method in the Bargmann representation. We evaluate the zeros for several examples. (author)
Primary Subject
Source
Mar 1999; 40 p; ISSN 0029-3865;
; 20 refs., 12 figs.; toscano at cbpf.br

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Report
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Truskova, N.F.
Joint Inst. for Nuclear Research, Dubna (Russian Federation). Lab. of Computing Techniques and Automation1996
Joint Inst. for Nuclear Research, Dubna (Russian Federation). Lab. of Computing Techniques and Automation1996
AbstractAbstract
[en] Use of a new expansion for Coulomb spheroidal functions together with already known expansions for them in a more convenient variant and also introduction of a new diagonal operator allow one to calculate eigenfunctions integrals of the two-centre problem analytically, in a simpler way. Due to that it requires considerably less time for calculation to obtain various matrix elements of discrete spectrum of the two-centre problem which are used for the solution of physical problems. (author)
Original Title
Vychislenie integralov zadachi dvukh tsentrov kvantovoj mekhaniki s pomoshch'yu analiticheskogo integrirovaniya
Primary Subject
Source
1996; 15 p; 24 refs. Submitted to Yadernaya Fizika.
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Report
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Suz'ko, A.A.; Velicheva, E.P.
Bogolyubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, Dubna (Russian Federation)1997
Bogolyubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, Dubna (Russian Federation)1997
AbstractAbstract
[en] The generalized technique of Bargmann potentials is elaborated for the reconstruction of time-dependent and time-independent two-dimensional potentials and the corresponding solutions in a closed analytic form on the basis of the inverse scattering problem in the adiabatic representation. A number of specific examples are considered within the parametric problem on the entire line and on the half-line. Matrix elements of an exchange interaction are calculated and studied in terms of obtained exact solutions of the parametric inverse problems
Primary Subject
Source
1997; 20 p; 26 refs., 8 figs. Submitted to the journal, Teoreticheskaya i Matematicheskaya Fizika.
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Report
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Barashenkov, I.V.; Smirnov, Yu.S.
Laboratory of Computing Techniques and Automation, Joint Institute for Nuclear Research, Dubna (Russian Federation)1997
Laboratory of Computing Techniques and Automation, Joint Institute for Nuclear Research, Dubna (Russian Federation)1997
AbstractAbstract
[en] The externally driven damped nonlinear Schroedinger (NLS) equation on the infinite line is studied. Existence and stability chart for its soliton solution is constructed on the plane of two control parameters, the forcing amplitude h and dissipation coefficient γ. For generic values of h and γ there are two coexisting solitons one of which (ψ+) is always unstable. The bifurcation diagram of the second solution (ψ-) depends on the dissipation coefficient: if γ<γcr, the ψ- is stable for small h and loses its stability via a Hopf bifurcation as h is increased; if γ>γcr, the ψ- is stable for all h. There are no 'stability windows' in the unstable region. We show that the previously reported 'stability windows' occur only when the equation is considered on a finite (and small) spatial interval
Primary Subject
Source
1997; 30 p; 19 refs., 16 figs., 1 tab.
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Report
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Achleitner, U.; Weihs, G.; Weinfurter, H.; Zeilinger, A.
46th annual symposium of the Austrian Physical Society. Programme and abstracts1996
46th annual symposium of the Austrian Physical Society. Programme and abstracts1996
AbstractAbstract
No abstract available
Original Title
Quantumzufallsgeneratoren
Primary Subject
Source
Schindler, H.G. (ed.); Oesterreichische Physikalische Gesellschaft, Vienna (Austria); 218 p; 1996; p. 64; 46. annual symposium of the Austrian Physical Society; 46. Jahrestagung der Oesterreichischen Physikalischen Gesellschaft; Linz (Austria); 23-27 Sep 1996
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Miscellaneous
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Conference
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Kostenko, B.F.; Yur'ev, M.Z.
Laboratory of Computing Techniques and Automation, Joint Institute for Nuclear Research, Dubna (Russian Federation)1998
Laboratory of Computing Techniques and Automation, Joint Institute for Nuclear Research, Dubna (Russian Federation)1998
AbstractAbstract
[en] The probability of observation of thermal and nuclear anomalies in PdDx is calculated assuming a physical mechanism of phonon laser type to take place. It is shown that poor reproducibility of these results has natural quantum mechanical explanation. (author)
Original Title
O nevosproizvodimosti teplovykh i yadernykh anomalij v dejteride palladiya
Primary Subject
Source
1998; 6 p; 8 refs. Submitted to Yadernaya Fizika
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Report
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Kostenko, B.F.
Laboratory of Computing Techniques and Automation, Joint Institute for Nuclear Research, Dubna (Russian Federation)1998
Laboratory of Computing Techniques and Automation, Joint Institute for Nuclear Research, Dubna (Russian Federation)1998
AbstractAbstract
[en] Methods of solution of the Schroedinger equation with non-Hermitian Hamiltonian H cap = H1 cap + iH2 cap, where Hi+ cap = Hi cap and [H1 cap, H2 cap] ≠ 0, are discussed using an exactly solvable quantum model. Some arguments about mathematical and physical consistency of the model are presented. A solution of Wigner's paradox concerning impossibility to describe selfreproducing systems in the frame of quantum mechanics is given. (author)
Original Title
Nekotorye metody resheniya uravneniya Shredingera s neehrmitovym gamil'tonianom vzaimodejstviya
Primary Subject
Source
1998; 14 p; 18 refs., 2 figs. Submitted to Yadernaya Fizika
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Report
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INIS VolumeINIS Volume
INIS IssueINIS Issue
Weihs, G.; Achleitner, U.; Jennewein, T.; Weinfurter, H.; Zeilinger, A.
47. annual symposium of the Austrian Physical Society1997
47. annual symposium of the Austrian Physical Society1997
AbstractAbstract
No abstract available
Original Title
Ein Test der Bellschen Ungleichungen mit unabhaengigen Beobachtern
Primary Subject
Source
Kutschera, W. (ed.); Oesterreichische Physikalische Gesellschaft, Vienna (Austria); 304 p; 1997; p. 202; 47. annual symposium of the Austrian Physical Society; 47. Jahrestagung der Oesterreichischen Physikalischen Gesellschaft; Vienna (Austria); 22-26 Sep 1997
Record Type
Miscellaneous
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Conference
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Sieber, M.; Paris-11 Univ., 91 - Orsay; Pavloff, N.; Schmit, C.
Paris-11 Univ., 91 - Orsay (France). Inst. de Physique Nucleaire1996
Paris-11 Univ., 91 - Orsay (France). Inst. de Physique Nucleaire1996
AbstractAbstract
[en] Contributions are derived to the trace formula for the spectral density accounting for the role of diffractive orbits in two-dimensional billiard systems with corners. This is achieved by using the exact Sommerfeld solution for the Green function of a wedge. A uniformly valid formula is obtained which interpolates between formerly separate approaches (the geometrical theory of diffraction and Gutzwiller's trace formula). It yields excellent numerical agreement with exact quantum results, also in cases where other methods fail. (author)
Primary Subject
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1996; [45 p.]; 34 refs.; Submitted to Physical Review, E (US).
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