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Full-Text Articles in Physics
Recurrences Associated With A Classical Orbit In The Node Of A Quantum Wave Function, John A. Shaw, John B. Delos, Michael Courtney, Daniel Kleppner
Recurrences Associated With A Classical Orbit In The Node Of A Quantum Wave Function, John A. Shaw, John B. Delos, Michael Courtney, Daniel Kleppner
Arts & Sciences Articles
Absorption spectra of atoms in magnetic fields reveal recurrences: manifestations of classical orbits (or quantum wave packets) that go out from the atom and later return. A formula from closed-orbit theory asserts that if the orbit lies on a node of the outgoing wave function, then the strength of the recurrence is zero. New quantum calculations, however, show that the recurrence strength is nonzero, though small. We derive a semiclassical formula for the recurrence strength associated with a classical orbit at a node of the quantum wave function. This formula is compared to the quantum mechanical calculation. Compared to …
Organization Of Sequences Of Bifurcations Of Periodic Orbits, D. A. Sadovskii, J. A. Shaw, John B. Delos
Organization Of Sequences Of Bifurcations Of Periodic Orbits, D. A. Sadovskii, J. A. Shaw, John B. Delos
Arts & Sciences Articles
Numerical calculations have shown that bifurcations of periodic orbits of Hamiltonian systems often occur in organized groups. Normal-form theory provides an explanation.
Closed Orbit Bifurcations In Continuum Stark Spectra, Michael Courtney, Hong Jiao, Neal Spellmeyer, Daniel Kleppner, J. Gao, John B. Delos
Closed Orbit Bifurcations In Continuum Stark Spectra, Michael Courtney, Hong Jiao, Neal Spellmeyer, Daniel Kleppner, J. Gao, John B. Delos
Arts & Sciences Articles
We report an experimental and theoretical study of the effect of bifurcations of closed classical orbits in continuum Stark spectra. Our findings provide a natural way to understand how the spectrum evolves from a simple sinusoidal modulation at positive energy to a quasidiscrete spectrum below the classical ionization limit. The experiment employs scaled-energy spectroscopy of lithium. The results provide the first experimental confirmation of a formulation of closed-orbit theory that provides a quantitative description of the behavior of the spectrum at a bifurcation.
Half-Cycle Pulse Acting On A One-Dimensional Rydberg Atom: Semiclassical Transition Amplitudes In Action And Angle Variables, C. D. Schwieters, John B. Delos
Half-Cycle Pulse Acting On A One-Dimensional Rydberg Atom: Semiclassical Transition Amplitudes In Action And Angle Variables, C. D. Schwieters, John B. Delos
Arts & Sciences Articles
In this paper we derive the expression for the transition coefficient used in the preceding paper [C. D. Schwieters and J. B. Delos, Phys. Rev. A 51, 1023 (1995)] for principal-quantum-number transitions in one-dimensional hydrogen caused by half-cycle pulses. We briefly review the methods of Miller [Adv. Chem. Phys. 25, 69 (1974)] and Marcus [Chem. Phys. Lett. 7, 525 (1970); J. Chem. Phys. 54, 3965 (1971)], and then derive the result using the methods of Maslov and Fedoriuk [Semi-Classical Approximation in Quantum Mechanics, (Reidel, Dordrecht, 1981)]. Also, we examine the approximate reduction of hydrogen …
Semiclassical Treatment Of A Half-Cycle Pulse Acting On A One-Dimensional Rydberg Atom, C. D. Schwieters, John B. Delos
Semiclassical Treatment Of A Half-Cycle Pulse Acting On A One-Dimensional Rydberg Atom, C. D. Schwieters, John B. Delos
Arts & Sciences Articles
The final-state distribution of hydrogen, acted upon by a 1/2-cycle pulse, has been calculated semiclassically for a proposed one-dimensional experiment. This work was motivated by the recent experimental realization of half-cycle pulses by Jones, You, and Bucksbaum [Phys. Rev. Lett. 70, 1236 (1993)] in which preliminary studies of ionization and state redistribution for hydrogenlike atoms were carried out. To simplify the situation theoretically, an experiment is proposed in which an additional weak static electric field is imposed and approximately one-dimensional states are selected. Within this one-dimensional approximation the transition probability to various n states (n is the principal …