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Magnetic polarization of the americium $J = 0$ ground state in AmFe$_{2}$

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 نشر من قبل Roberto Caciuffo
 تاريخ النشر 2015
  مجال البحث فيزياء
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Trivalent americium has a non-magnetic ($J$ = 0) ground state arising from the cancelation of the orbital and spin moments. However, magnetism can be induced by a large molecular field if Am$^{3+}$ is embedded in a ferromagnetic matrix. Using the technique of x-ray magnetic circular dichroism, we show that this is the case in AmFe$_2$. Since $langle J_z rangle$ = 0, the spin component is exactly twice as large as the orbital one, the total Am moment is opposite to that of Fe, and the magnetic dipole operator $langle T_{z} rangle$ can be determined directly; we discuss the progression of the latter across the actinide series.



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