A thermal beam of helium (2 3 S 1 ) metastable atoms was used to excite coherently the 2 P 3/2 levels of Ca, Sr and Ba in a Penning ionising collision. The coherent excitation of the ions appears as a linear polarisation of the optical emission from the excited ions. The degree of linear polarisation is 5.5, 3.5 and 0.5% for Ca, Sr and Ba, respectively, with the polarisation parallel to the beam direction. Hanle effect signals from the 2 P 3/2 level of Sr were observed and the radioactive decay rate measured.A thermal beam of helium (2 3 S 1 ) metastable atoms was used to excite coherently the 2 P 3/2 levels of Ca, Sr and Ba in a Penning ionising collision. The coherent excitation of the ions appears as a linear polarisation of the optical emission from the excited ions. The degree of linear polarisation is 5.5, 3.5 and 0.5% for Ca, Sr and Ba, respectively, with the polarisation parallel to the beam direction. Hanle effect signals from the 2 P 3/2 level of Sr were observed and the radioactive decay rate measured.

Journal of Physics B Atomic and Molecular PhysicsOct 28, 19795 citations

Anomalous Population Distributions in an Optically Excited Metastable Level in Ca F2 : Tm2+

Charles H. Anderson, Edward S. Sabisky

The population distribution among the magnetic sublevels of the metastable state of Ca ${\mathrm{F}}_{2}$ : ${\mathrm{Tm}}^{2+}$ is shown to be strongly influenced by spin orientation memory from the ground state. This memory is dependent on the wavelength and polarization of the pump radiation, being quite strong at 5790 \AA{}. The population is also influenced by an optical cross-relaxation or excitation transfer between neighboring ions, particularly so because the hyperfine splittings in the ground and excited states are almost identical. Also, it is shown that there is a high degree of nuclear spin orientation memory.The population distribution among the magnetic sublevels of the metastable state of Ca${\mathrm{F}}_{2}$: ${\mathrm{Tm}}^{2+}$ is shown to be strongly influenced by spin orientation memory from the ground state. This memory is dependent on the wavelength and polarization of the pump radiation, being quite strong at 5790 \AA{}. The population is also influenced by an optical cross-relaxation or excitation transfer between neighboring ions, particularly so because the hyperfine splittings in the ground and excited states are almost identical. Also, it is shown that there is a high degree of nuclear spin orientation memory.

Physical ReviewFeb 10, 196920 citations

The population distribution among the magnetic sublevels of the metastable state of Ca

{\mathrm{F}}_{2}

{\mathrm{Tm}}^{2+}

is shown to be strongly influenced by spin orientation memory from the ground state. This memory is dependent on the wavelength and polarization of the pump radiation, being quite strong at 5790 \AA{}. The population is also influenced by an optical cross-relaxation or excitation transfer between neighboring ions, particularly so because the hyperfine splittings in the ground and excited states are almost identical. Also, it is shown that there is a high degree of nuclear spin orientation memory.