We experimentally study energy-pooling collision in the Rb–Cs vapour mixture at low densities in a cell. Atoms are excited to Rb(5 P 1/2 ) and Cs(6 P 3/2 ) states using two single-mode diode lasers. To isolate the heteronuclear contribution in the fluorescence spectrum, a double-modulation technique is adopted. The excited-atom density and spatial distribution are mapped by monitoring the absorption of a counterpropagating single-mode diode laser beam, tuned to Rb(5 P 1/2 →7 S 1/2 ) and Cs(6 P 3/2 →8 S 1/2 ) transitions, respectively, which could be translated parallel to the pump beams. The excited atom densities are combined with the measured fluorescence ratios to determine cross section for the energy-pooling process [i.e. Rb(5 P 1/2 ) + Cs (6 P 3/2 ) → Cs(8 S 1/2 ) + Rb (5 S 1/2 )]. The cross section is 3.79×10 −14 cm 2 ±45%.
We experimentally study energy-pooling collision in the Rb–Cs vapour mixture at low densities in a cell. Atoms are excited to Rb(5 P 1/2 ) and Cs(6 P 3/2 ) states using two single-mode diode lasers. To isolate the heteronuclear contribution in the fluorescence spectrum, a double-modulation technique is adopted. The excited-atom density and spatial distribution are mapped by monitoring the absorption of a counterpropagating single-mode diode laser beam, tuned to Rb(5 P 1/2 →7 S 1/2 ) and Cs(6 P 3/2 →8 S 1/2 ) transitions, respectively, which could be translated parallel to the pump beams. The excited atom densities are combined with the measured fluorescence ratios to determine cross section for the energy-pooling process [i.e. Rb(5 P 1/2 ) + Cs (6 P 3/2 ) → Cs(8 S 1/2 ) + Rb (5 S 1/2 )]. The cross section is 3.79×10 −14 cm 2 ±45%.
Rate coefficients for energy-pooling (EP) collisions Rb(5P_(J))+Cs(6P_(3/2))-->Rb(5S_(1/2))+Cs(nl_(J')) have been measured. Atoms were excited to Rb(5P_(J)) and Cs(6P_(3/2)) states using two single-mode diode lasers. To isolate the heteronuclear contribution in the fluorescence spectrum, a double-modulation technique has been adopted. The excited-atom density and spatial distribution are mapped by monitoring the absorption of a counterpropagating single-mode diode laser beam, tuned to Rb(5P_(J)-->7S_(1/2)) and Cs(6P_(3/2)-->8S_(1/2)) transitions respectively, which could be translated parallelly to the pump beams. The excited atom densities are combined with the measured fluorescence ratios to determine cross sections for the EP processes. It was found that Rb(5P_(J))+Cs(6P_(3/2)) collisions are more efficient than Rb(5P_(3/2))+Cs(6P_(3/2)) collisions for populating Cs(4F_(5/2)), while the opposite is true for populating Cs(4F_(7/2)).
Rate coefficients for energy-pooling (EP) collisions Rb(5PJ) + Cs(6P3/2)→Rb(5S1/2) + Cs(nlJ’) have been measured. Atoms were excited to Rb(5PJ) and Cs(6P3/2) states using two single-mode diode lasers. To isolate the heteronuclear contribution in the fluorescence spectrum, a double-modulation technique has been adopted. The excited-atom density and spatial distribution are mapped by monitoring the absorption of a counterpropagating single-mode diode laser beam, tuned to Rb(5PJ→7S1/2) and Cs(6P3/2→8S1/2) transitions respectively, which could be translated parallelly to the pump beams. The excited atom densities are combined with the measured fluorescence ratios to determine cross sections for the EP processes. It was found that Rb(5P1/2) + Cs(6P3/2) collisions are more efficient than Rb(5P3/2) + Cs(6P3/2) collisions for populating Cs(4F5/2), while the opposite is true for populating Cs(4F7/2).更多还原
We experimentally study rubidium energy pooling collisions of Rb(5 P 3/2 )+Rb(5 P 3/2 )→Rb(5 S 1/2 )+Rb ( nl J = 5 D J ,7 S 1/2 ) at low densities in a cell using diode laser excitation. The excited-atom density and spatial distribution are mapped by monitoring the absorption of a counterpropagating single-mode diode laser beam, tuned to the 5 P 3/2 →7 S 1/2 transition, which could be translated parallel to the pump beam. The excited atom densities are combined with measured fluorescence ratios to determine cross sections for the rubidium energy pooling process. The cross sections for nl J being 5 D 5/2 , 5 D 3/2 , and 7 S 1/2 are (1.32±0.59) × 10 −14 , (1.18±0.53) × 10 −14 and (3.21±1.44) × 10 −15 cm 2 , respectively.
An experimental study of rubidium energy pooling collisions,5P_J+5P_J′→5S+5D_J″,at thermal energies,has been carried out in a cell.Atoms were excited to either the 5P_1/2 or 5P_3/2 state using a single-mode diode laser.The excited-atom density and spatial distribution were mapped by monitoring the absorption of a counterpropagating single-mode diode laser beam,tuned to either 5P_1/2→5D_3/2,5P_3/2→7S_1/2 transition,which could be translated parallel to the pump beam.The excited atom densities are combined with measured fluorescence ratios to determine cross sections for the rubidium energy pooling process 5P_J+5P_J′→5S+5D_J″.Two tunable cw diode lasers were used to excite 5P_1/2 and 5P_3/2 respectively and the 5D_J″→5P_J fluorescence intensities were measured.For 5P_3/2+5P_1/2 collisions the cross sections for 5D_5/2,5D_3/2 are(1.12±0.50)×10~-14 and(1.01±0.45)×10~-14 cm~2,respectively.
An experimental study of rubidium energy pooling collisions, Rb(5P(J)) + Rb(5P(J))-->Rb(nlJ') + Rb(5S), at thermal energies, was carried out in a cell. Atoms were excited to either the 5P 1/2 or 5P 3/2 state using a single-mode diode laser. The excited atom density and spatial distribution were mapped by monitoring the absorption of a counter-propagating single-mode diode laser beam, tuned to either 5P 1/2-->5D 3/2 or 5P 3/2-->7S 1/2 transition, which could be translated parallel to the pump beam. The excited atom densities were combined with the measured fluorescence ratios to determine cross sections for the rubidium energy pooling process. For 5P 3/2 excitation the cross sections for nlJ' being 5D 5/2, 5D 3/2, and 7S 1/2 are (1.32+/-0.59) x 10(-14), (1.18+/-0.53) x 10(-14) and (3. 21+/-1. 44) x 10(-15) cm2, respectively. For 5P 1/2 excitation the cross sections for nlJ' being 5D 5/2 and 5D 3/2 are (6.57+/-2.96) x 10(-15), and (5.90+/-2.66) x 10(-15) cm2, respectively. The results were compared with those of other experiments.
Using stepwise excitation of the cesium 8S atoms level in Cs vapor,several collisional and radiative processes have been identified from the intensities and spectra of the Cs fluorescence.The 5D state was populated by 8S→7P→5D transitions.In cesium densities 1016-1017?cm-3,the energy pooling collisions 5D+5D→nL+6S(nL=9D,11S,7F are studied.Since the 5D→6P(3.0-3.6 μm) fluorescence could not be detected with this experiment,the EP rate coefficients have been measured relative to the known rate coefficient of the collision,i.e.,6P+5D→6S+7D.The excited-atom density and spatial distribution were mapped by monitoring the absorption of a counterpropagating single-mode laser beam,tuned to 6P3/2→8S1/2 transition,which could be translated parallel to the pump beam.The excited atom densities are combined with measured fluorescene ratios to determine cross sections for the cesium energy pooling process.The average values(in units of 10-10?cm3s-1) for nL=9D,11S and 7F are 8.4±4.2,7.3±3.6,and 9.7±4.8,respectively.Influence on k11S and k7F of the energy transfer process 11S+6S7F+6S is also dicussed.