Rubidium Rydberg atoms in strong static fields

Abstract

A report on experiments performed in Munich on Rydberg atoms in strong static fields is presented. These include high-resolution laser spectroscopy and wavepacket generation and detection. The results are mainly interpreted by semiclassical techniques. Using the Fourier analysis of high-resolution scaled spectra in strong crossed electric and magnetic fields, quasi-Landau resonances in a particular parameter range are investigated. The problem of singularities in the semiclassical models describing the quasi-Landau spectra is discussed, and a qualitative solution to this problem is given. Rydberg wavepackets in strong magnetic fields were investigated. For this purpose Rydberg atoms are excited by pairs of time-separated short UV laser pulses. In these experiments the superior performance of a recently proposed technique is demonstrated. The obtained results for strong magnetic fields are interpreted semiclassically. Wavepacket propagation along a particular quasi-Landau orbit is clearly identified. In the last part of the paper, properties of high angular momentum Rydberg atoms in strong crossed electric and magnetic fields are discussed. The classically regular motion in that regime corresponds to situations well known from the motion of charged particles in Penning traps. A simple method for the preparation and isolation of this type of Rydberg atom is presented.