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arXiv · 2008.09182

Quantum versus classical chirps in a Rydberg atom

Tsafrir Armon·Lazar Friedland
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Abstract

The interplay between quantum-mechanical and classical evolutions in a chirped driven Rydberg atom is discussed. It is shown that the system allows two continuing resonant excitation mechanisms, i.e., a successive two-level transitions (ladder climbing) and a continuing classical-like nonlinear phase locking (autoresonance). The persistent $1:1$ and $2:1$ resonances between the driving and the Keplerian frequencies are studied in detail and characterized in terms of two dimensionless parameters $P_{1,2}$ representing the driving strength and the nonlinearity in the problem, respectively. The quantum-mechanical rotating wave and the classical single resonance approximations are used to describe the regimes of efficient classical or quantum-mechanical excitation in this two-parameter space.

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Tsafrir Armon, Lazar Friedland. 2020-11-19. Quantum versus classical chirps in a Rydberg atom. https://doi.org/10.1103/physreva.102.052817

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