Alkaline earth Rydberg state

Three different methods have been used to make microwave resonance measurements of intervals between alkaline earth Rydberg states. In all of these measurements state selective laser excitation of alkaline earth atoms in a beam was combined with one of three forms of state selective ionization of the final states. 

Perhaps the most interesting aspect of microwave spectroscopy of alkaline earth Rydberg states is that it affords easy access to the nonadiabatic effects in core polarization, and such experiments have been done with both Ca6 and Ba.3... 

Purely optical excitation is possible for alkali and alkaline earth atoms. For most other atoms the transition from the ground state to any other level is at too short a wavelength to be useful. To produce Rydberg states of such atoms a combination of collisional and optical excitation is quite effective. A good example is the study of the Rydberg states of Xe by Stebbings et al.24 As shown in Fig. 3.5, a thermal beam of Xe atoms is excited by electron impact, and a reasonable fraction of the excited atoms is left in the metastable state. Downstream from the electron excitation the atoms in the metastable state are excited to a Rydberg state by pulsed dye laser excitation. 

In this chapter we have implicitly assumed the Rydberg atom to be a one electron-atom. In the perturbed Rydberg series of, for example, alkaline earth atoms, Rydberg states can have mixed valence-Rydberg character. In such states the black body effects are reduced by a factor equal to the fractional Rydberg character.14... 

HYPERFINE STRUCTURE AND ISOTOPE SHIFTS OF RYDBERG STATES IN ALKALINE EARTH ATOMS... 

Much effort has been invested to obtain a complete understanding of the detailed structure of Rydberg states of alkaline-earth atoms. In parallel to the experimental mapping of states went a successful parametrization of the observed spectra by the Multichannel Quantum Defect Theory (MQDT). The paper by Cooke presented at the last ICAP described the basic aspects of this approach. Specifically, the level structure was measured and analysed by MQDT for odd ... 

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