ZHANG Jing, SHEN Li, DAI Chang-jian. Field Ionization of Eu Rydberg States[J]. Chinese Journal of Luminescence, 2015,36(7): 757-762 DOI: 10.3788/fgxb20153607.0757.
p Rydberg states converging to the first ionization limit 4f
7
6s
9
S
4
was systematically investigated. Firstly
the spectra of Rydberg states 4f
7
6s
n
p of Eu atom were measured using the three-step laser excitation and electric field ionization (EFI) method. Secondly
the EFI pulse(pulse width of 0.2 s)was applied after laser excitation. Then
we continuously scan field ionization voltage to observe the EFI process
and to realize the potential of field ionization we need to understand what happens to the atoms as the pulse field rises from 0 to 3 kV. The exact location of ionization threshold can be obtained when the peak of ionization field changes. Especially
above the threshold
some structures are found due to black body radiation (BBR).
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references
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