Stark effect in atomic hydrogen

The advent of tunable lasers created a radically new situation as to the possibility for selective excitation of high Rydberg states and for making precise measurements on their properties. Highly excited atoms are very sensitive to external fields, and currently used field ionization methods are very powerful for detecting Rydberg states. As a consequence of these circumstances, such an old problem as the Stark effect in atomic hydrogen attracted a renewed interest. 

Figure 2.10 -trajectories for the resonance energy (Stark effect in the hydrogen atom), where N is the number of basis functions per /-value, for more details see Ref. [67]. Taken from Reinhardt [67] with permission of IJQC. 

M. Hehenberger, H.V. McIntosh, E. Brandas, Weyl s Theory Applied to the Stark Effect in the Hydrogen Atom, Phys. Rev. A10 (1974) 1494. 

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