Laser photoionization detection of individual sodium atoms via Rydberg states

Collisional and thermal ionization of sodium n S and n D Rydberg atoms with n = 8–20 has been studied. The experiments were performed using a two-step pulsed laser excitation in an effusive atomic beam at atom density of about 2 × 10 10 cm −3 . Molecular and atomic ions from associative, Penning and thermal ionization processes were detected. It was found that the atomic ions were created mainly due to photoionization of Rydberg atoms by photons of blackbody radiation at the ambient temperature of 300 K. Blackbody ionization rates and effective lifetimes of Rydberg states of interest were determined. The molecular ions were found to be from associative ionization in Na( nL ) + Na(3S) collisions. Rate constants of associative ionization have been measured using an original method based on relative measurements of Na + 2 and Na + ion signals.Collisional and thermal ionization of sodium n S and n D Rydberg atoms with n = 8–20 has been studied. The experiments were performed using a two-step pulsed laser excitation in an effusive atomic beam at atom density of about 2 × 10 10 cm −3 . Molecular and atomic ions from associative, Penning and thermal ionization processes were detected. It was found that the atomic ions were created mainly due to photoionization of Rydberg atoms by photons of blackbody radiation at the ambient temperature of 300 K. Blackbody ionization rates and effective lifetimes of Rydberg states of interest were determined. The molecular ions were found to be from associative ionization in Na( nL ) + Na(3S) collisions. Rate constants of associative ionization have been measured using an original method based on relative measurements of Na + 2 and Na + ion signals.

arXiv:physics/0501088Journal of Physics B Atomic Molecular and Optical PhysicsJan 6, 200523 citations

Ion formation in sodium vapor containing Rydberg atoms

C. Burkhardt, W. P. Garver, Vikram S. Kushawaha +1 more

The formation of ${\mathrm{Na}}^{+}$ and ${\mathrm{Na}}_{2}^{+}$ in sodium vapor (\ensuremath{\sim} ${10}^{11}$ - ${10}^{13}$ ${\mathrm{cm}}^{\ensuremath{-}3}$) containing laser-selected Rydberg atoms $(15<~n<~35)$ has been studied. At low atom densities photoionization, collisional ionization, and associative ionization dominate, but more-complicated mechanisms contribute to the ion yield at higher densities.The formation of ${\mathrm{Na}}^{+}$ and ${\mathrm{Na}}_{2}^{+}$ in sodium vapor (\ensuremath{\sim}${10}^{11}$-${10}^{13}$ ${\mathrm{cm}}^{\ensuremath{-}3}$) containing laser-selected Rydberg atoms $(15<~n<~35)$ has been studied. At low atom densities photoionization, collisional ionization, and associative ionization dominate, but more-complicated mechanisms contribute to the ion yield at higher densities.

Physical Review AJul 1, 198416 citations

The formation of

{\mathrm{Na}}^{+}

and

{\mathrm{Na}}_{2}^{+}

in sodium vapor (\ensuremath{\sim}

{10}^{11}

{10}^{13}

${\mathrm{cm}}^{\ensuremath{-}3}$) containing laser-selected Rydberg atoms

(15<~n<~35)

has been studied. At low atom densities photoionization, collisional ionization, and associative ionization dominate, but more-complicated mechanisms contribute to the ion yield at higher densities.