Laser manipulation of nuclear transitions: experiment

Olga Kocharovskaya, Roman Kolesov, Elena Kuznetsova, Yuri Rostovtsev, Farit Vagizov Texas A&M University, College Station, TX and Silviu Olariu National Institute of Physics and Nuclear Engineering, Magurele, Bucharest, Romania

Nuclear and electronic transitions of 151 Eu

Calculated Mossbauer spectra of Eu 3+ :CaF 2 for the ground 7 F 0 and excited 5 D 0 electronic states

Quadrupole interactions between the 151 Eu nucleus and the 7 F 0, 5 D 0 electronic states in Eu 3+ :CaF 2 Quadrupole interaction: H Q = P[I z 2 – I(I+1)/3 +  (I + 2 +I - 2 )/6], I: angular momentum of nucleus, P: quadrupole constant,  : asymmetry parameter P = 3eQV zz /4I(2I-1) Q: nuclear quadrupole moment, V zz : electric field gradient Q g = 1.16 b, Q e = 1.6 b, Ig = 5/2, Ie = 7/2

Comparison of Mossbauer spectra for ground and excited optical states of 151 Eu 3+ Isomer shift  E M : difference in the energy of the  rays emitted by the 151 Eu nuclei when the electrons are in the 7 F 0 and respectively the 5 D 0 states Isotopic shift  E O : difference in the energy of the optical 7 F D 0 transitions for the 151 Eu and respectively the 153 Eu isotopes  E M /  E O =  M /  g  M : variation of the square of the nuclear radius between the 21.5 keV state and the ground nuclear state of 151 Eu  g : variation of the square of the nuclear radius between the 153 Eu and the 151 Eu nuclei  E O = 0.15 GHz,  M =0.019 fm 2,  g = fm 2, 1 fm = m:  E M = 5.2 MHz

Calculated Mossbauer spectra for a 17.6% population in the 5 D 0 electronic state and a 6 MHz isomer shift

Magnitude of the effect

Optical absorption in the Eu 3+ :CaF 2 sample

Fluorescence of the Eu 3+ :CaF 2 sample

Fluorescence of the Eu 3+ :CaF 2 sample for 532 nm excitation

Eu 3+ centers in CaF 2, according to van der Voort et al. (1992)

Effects of 532 nm laser radiation on the Mossbauer spectra of a 151 Eu 3+ :CaF 2 sample

Count difference between the Mossbauer spectra of the 151 Eu 3+ :CaF 2 sample with laser on and off

Comparison of the relative positions of the extremal points for the calculated and measured Mossbauer spectra

Excitation spectra of the emission at nm (red line) and at nm (olive line), at liquid helium temperature, for Eu 3+ :CaF 2, according to van der Voort et al. (1992)

End of the presentation

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