Isotope selective three-step photoionization of ¹⁷⁶Lu

Abstract

Numerical computations of ionization efficiency and isotope selectivity of 176 L u have been carried out for the following three-step ladder type photoionization scheme, 5 d 6 s 2 2 D 3 / 2 ( 0.0 c m − 1 ) − − − ⟶ 540.4068 n m ⁡ 5 d 6 s 6 p 4 F 5 / 2 o ( 18504.58 c m − 1 ) − − − ⟶ 535.0626 n m 5 d 6 s 7 s 4 D 3 / 2 ( 37193.98 c m − 1 ) − − − ⟶ 618.0061 n m 53375 c m − 1 A u t o i o n i z a t i o n S t a t e → L u + , by invoking the density matrix formalism for the laser–atom interactions. Equations of motion have been derived for the odd isotopes by inclusion of hyperfine levels. The line shapes and their effect on the ionization efficiency and isotope selectivity have been discussed in detail. The effects of power of excitation and ionization lasers, spectral bandwidths, pulse delays, Doppler broadening of the atomic ensemble on the ionization efficiency, and degree of enrichment have been presented. Optimum conditions for the power of excitation, detunings, and other system parameters for the selective yet efficient photoionization of 176 L u have been identified.

Isotope separation of 176Lu a precursor to 177Lu medical isotope using broadband lasers

“…The results obtained were in good agreement with the experimental results 14 . The optimum conditions for the isotope selective photoionization of 176 Lu have been derived.…”

“…The present results are compared with the previously reported 5 , 14 values in Table 5 . For the case of lasers with bandwidth of 100 MHz, even for the maximum possible half angular divergence value (90°), the degree of enrichment is found to be > 99%, which is nearly 3 times higher than the previously reported 540–535 nm scheme by D’yachkov 5 et al It is not possible to enrich the 176 Lu isotope > 5% using broadband lasers having a width of 500 MHz using the 540–535 nm photoionization scheme.…”

“…The ionization efficiency of 0.2 corresponds to the ionization of 80% of population available at the ground hyperfine level 17/2. In order to compare the present results with the previously reported data 5 , 14 , production rates have been calculated for the atomic number density of 5 × 10 14 of Lu corresponding to the number density of 1.3 × 10 13 for 176 Lu. Further, the laser-atom interaction length is considered as 200 mm with a diameter of 10 mm.…”

“…Enhanced ionization observed at the intersection of horizontal and vertical ridges correspond either to the hyperfine pathway (numbered as per the Table 2 ) or crossovers. Origin of such crossovers has been discussed in detail in a recent article 14 . The resonance position of the 17/2–17/2–19/2 of 176 Lu has been shown as a “filled circle” in the 175 Lu two-dimensional contour plot in Fig.…”

Laser isotope separation of 176Lu through off-the-shelf lasers

“…Since the mass shift is also small for the adjacent isotopes of mid and high-z elements, the overall isotope shift is small. Fortunately, in case of Lutetium, both We have recently studied 8 the isotope selective photoionization of 176 Lu and optimization of the process conditions for the enrichment of 176 Lu through the above photoionization scheme using density matrix formalism. The obtained results were in good agreement with the reported experimental data 7 .…”