In simple one-photon ionization, decoherence occurs due to entanglement between ion and photoelectron. Therefore, the preparation of coherent superpositions of electronic eigenstates of the hole in the photoion is extremely difficult. We demonstrate for the xenon atom that the degree of electronic coherence of the photoion in attosecond photoionization can be enhanced if the influence of many-body interactions is properly controlled. A mechanism at low photon energies involving multiphoton ionization is found, suppressing the loss of coherence through ionization into the same photoelectron partial waves. The degree of coherence found between the $4{d}_{0}$ and $5s$ hole states is, on the one hand, limited by Auger decay of the $4{d}_{0}$ hole. On the other hand, increasing the population ratio such that a significant portion of the state is in a true superposition of both states renders the maximization of the degree of coherence difficult.In simple one-photon ionization, decoherence occurs due to entanglement between ion and photoelectron. Therefore, the preparation of coherent superpositions of electronic eigenstates of the hole in the photoion is extremely difficult. We demonstrate for the xenon atom that the degree of electronic coherence of the photoion in attosecond photoionization can be enhanced if the influence of many-body interactions is properly controlled. A mechanism at low photon energies involving multiphoton ionization is found, suppressing the loss of coherence through ionization into the same photoelectron partial waves. The degree of coherence found between the $4{d}_{0}$ and $5s$ hole states is, on the one hand, limited by Auger decay of the $4{d}_{0}$ hole. On the other hand, increasing the population ratio such that a significant portion of the state is in a true superposition of both states renders the maximization of the degree of coherence difficult.

Physical Review AApr 13, 20204 citations

Shift of holes in spectral lines due to time dependent perturbation

R. P. Srivastava

The radiative decay of an atom with two excited states, one decaying and the other non-decaying, coupled by a time dependent perturbation, is investigated. The hole in the emission line is found to be shifted by an amount equal to the frequency of the time dependent perturbation. The practical importance of this effect is discussed. It is also noticed that the two methods of solution, one by making the rotating-wave approximation and the other by a perturbation expansion, yield different results, especially in the case when the two excited states are strongly coupled.The radiative decay of an atom with two excited states, one decaying and the other non-decaying, coupled by a time dependent perturbation, is investigated. The hole in the emission line is found to be shifted by an amount equal to the frequency of the time dependent perturbation. The practical importance of this effect is discussed. It is also noticed that the two methods of solution, one by making the rotating-wave approximation and the other by a perturbation expansion, yield different results, especially in the case when the two excited states are strongly coupled.

Canadian Journal of PhysicsDec 15, 19761 citation

Two-photon decay of highly excited states

Viktor K. Dubrovich

Optics and SpectroscopyAug 1, 19871 citation

4{d}_{0}

and

5s

hole states is, on the one hand, limited by Auger decay of the

4{d}_{0}

hole. On the other hand, increasing the population ratio such that a significant portion of the state is in a true superposition of both states renders the maximization of the degree of coherence difficult.