Laser-enhanced ionization spectroscopy of mercury Rydberg states

The spectral characteristics of mercury Rydberg states (n = 10-42) were observed and studied. Each principal quantum number was observed as a tripler, and after observing a quarter of lines for n = 10, 11, and 12, these lines were assigned, from red to blue, as belonging to upper levels P-1(1)0, P-3(2)0, P-3(1)0, and P-3(0)0. These levels were studied as a function of variable applied high voltage (between the electrodes) and variable buffer gas pressure. In this way, the broadening and splitting caused by the influence of Stark effects and of increasing buffer gas pressure were observed for different n values. These observations will allow one to choose the optimal level for excitation, as well as the optimal operating conditions in terms of pressure and applied high voltage, for obtaining the best sensitivity and limit of detection by analytical laser-enhanced ionization spectroscopy. (C) 1997 Elsevier Science B.V.