Distribution of absorbed photons in the tunneling ionization process

• Published in: Scientific reports Vol. 11; no. 1; p. 3956
• Main Authors: Ivanov, I. A., Kim, Kyung Taec
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 17-02-2021; Nature Publishing Group; Nature Portfolio
• Subjects: 639/766/36/1121; 639/766/483/1139; Asymmetry; Electromagnetic fields; Electromagnetism; Hilbert space; Humanities and Social Sciences; Ionization; Lasers; multidisciplinary; Photons; Radiation; Science; Science (multidisciplinary); Stochastic models; Stochastic processes; Stochasticity
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-021-83453-0

We describe a procedure that allows us to solve the three-dimensional time-dependent Schrödinger equation for an atom interacting with a quantized one-mode electromagnetic field. Atom-field interaction is treated in an ab initio way prescribed by quantum electrodynamics. We use the procedure to calculate probability distributions of absorbed photons in the regime of tunneling ionization. We analyze evolution of the reduced photon density matrix describing the state of the field. We show that non-diagonal density matrix elements decay quickly, as a result of the decoherence process. A stochastic model, viewing ionization as a Markovian birth-death process, reproduces the main features of the calculated photon distributions.