Methods of excitation and analysis of double-Rydberg states of the neutral barium atom are discussed. Spectra of 9dn′d double-Rydberg series of barium are studied and interpreted in a two-channel quantum-defect model. An example of stabilization for the 9d5/227d state is shown. We propose a new investigative method for Rydberg levels of the Ba+ ion that is based on a microwave-ionization process coupled with a double time-of-flight mass spectrometer. This novel setup permits us to obtain initial experimental evidence of highly excited double-Rydberg states, 26dn′p and 27sn′p (n′ ≳ 45), of the barium atom.Methods of excitation and analysis of double-Rydberg states of the neutral barium atom are discussed. Spectra of 9dn′d double-Rydberg series of barium are studied and interpreted in a two-channel quantum-defect model. An example of stabilization for the 9d5/227d state is shown. We propose a new investigative method for Rydberg levels of the Ba+ ion that is based on a microwave-ionization process coupled with a double time-of-flight mass spectrometer. This novel setup permits us to obtain initial experimental evidence of highly excited double-Rydberg states, 26dn′p and 27sn′p (n′ ≳ 45), of the barium atom.

Journal of the Optical Society of America BMay 1, 198743 citations

Improved dipole transition strengths in Ba^+ from Ba Rydberg spectroscopy

Shannon L. Woods, S. R. Lundeen, Erica L. Snow

Bulletin of the American Physical SocietyMay 29, 20100 citations

Determination of dipole and quadrupole polarizabilities of Ba+ by measurement of the fine structure of high- L n=9 and 10 Rydberg states of barium

Erica L. Snow, M. A. Gearba, R. A. Komara +2 more

The fine structure of high-angular-momentum $n=9$ and 10 Rydberg states of barium has been measured precisely, using the resonant excitation Stark ionization spectroscopy method. Optical transitions corresponding to $(n,{n}^{\ensuremath{'}})=(10,30)$, (9,17), and (9,20) were induced with a Doppler-tuned ${\mathrm{CO}}_{2}$ laser, determining the fine-structure energies corresponding to all $n=9$ and 10 levels with $L\ensuremath{\geqslant}6$. The pattern of these fine-structure energies conforms closely with an effective potential model, by comparison with which the dipole and quadrupole polarizabilities of ${\mathrm{Ba}}^{+}$ can be determined. Combining our data with earlier measurements made it possible to deduce, in addition, the portion of ${\ensuremath{\alpha}}_{2}$ due to the lowest excited $D$ state of ${\mathrm{Ba}}^{+}$ . Our best estimates of these three properties are ${\ensuremath{\alpha}}_{1}=124.30(16){a}_{0}^{3}$, ${\ensuremath{\alpha}}_{2}=2462(361){a}_{0}^{5}$, and ${\ensuremath{\alpha}}_{2}^{0}=1828(88){a}_{0}^{5}$.The fine structure of high-angular-momentum $n=9$ and 10 Rydberg states of barium has been measured precisely, using the resonant excitation Stark ionization spectroscopy method. Optical transitions corresponding to $(n,{n}^{\ensuremath{'}})=(10,30)$, (9,17), and (9,20) were induced with a Doppler-tuned ${\mathrm{CO}}_{2}$ laser, determining the fine-structure energies corresponding to all $n=9$ and 10 levels with $L\ensuremath{\geqslant}6$. The pattern of these fine-structure energies conforms closely with an effective potential model, by comparison with which the dipole and quadrupole polarizabilities of ${\mathrm{Ba}}^{+}$ can be determined. Combining our data with earlier measurements made it possible to deduce, in addition, the portion of ${\ensuremath{\alpha}}_{2}$ due to the lowest excited $D$ state of ${\mathrm{Ba}}^{+}$. Our best estimates of these three properties are ${\ensuremath{\alpha}}_{1}=124.30(16){a}_{0}^{3}$, ${\ensuremath{\alpha}}_{2}=2462(361){a}_{0}^{5}$, and ${\ensuremath{\alpha}}_{2}^{0}=1828(88){a}_{0}^{5}$.

Physical Review AFeb 25, 200529 citations

Measurements in high-L, n=17 and 20 Rydberg states of barium: An investigation of ion core properties of Ba

^{+}

The fine structure of high-angular-momentum

n=9

and 10 Rydberg states of barium has been measured precisely, using the resonant excitation Stark ionization spectroscopy method. Optical transitions corresponding to $(n,{n}^{\ensuremath{'}})=(10,30)$, (9,17), and (9,20) were induced with a Doppler-tuned

{\mathrm{CO}}_{2}

laser, determining the fine-structure energies corresponding to all

n=9

and 10 levels with $L\ensuremath{\geqslant}6$. The pattern of these fine-structure energies conforms closely with an effective potential model, by comparison with which the dipole and quadrupole polarizabilities of

{\mathrm{Ba}}^{+}

can be determined. Combining our data with earlier measurements made it possible to deduce, in addition, the portion of ${\ensuremath{\alpha}}_{2}$ due to the lowest excited

D

state of

{\mathrm{Ba}}^{+}

. Our best estimates of these three properties are ${\ensuremath{\alpha}}_{1}=124.30(16){a}_{0}^{3}$, ${\ensuremath{\alpha}}_{2}=2462(361){a}_{0}^{5}$, and ${\ensuremath{\alpha}}_{2}^{0}=1828(88){a}_{0}^{5}$.