INITIAL CONDITIONS OF CLOSED CLASSICAL ORBITS FROM QUANTUM SPECTRA

A method is presented for determining the initial conditions of classi cal orbits from the quantum spectra of the diamagnetic hydrogen atom. Each classical trajectory which is closed at the nucleus produces a si nusoidal fluctuation in the photoabsorption spectrum, The amplitude of each orbit's contribution appears in the Fourier transform of a spect rum computed at constant scaled energy. For a given initial state, clo sed-orbit theory gives the dependence of this recurrence amplitude on the initial angle of an orbit. By comparing the recurrence amplitudes for different initial states, the initial conditions of closed classic al orbits are determined from quantum spectra. (C) 1996 American Insti tute of Physics.