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تسجيل مستخدم جديدElectronic structures of UTSn (T=Ni, Pd) using photoemission spectroscopy
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The electronic structures of the localized $5f$ systems UTSn (T=Ni, Pd) have been investigated using photoemission spectroscopy (PES). The extracted U $5f$ PES spectra of UTSn (T=Ni, Pd) exhibit a broad peak centered at $sim 0.3$ eV below $rm E_F$ with rather small spectral weight near $rm E_F$ (N$_f$($rm E_F$)). The small N$_f$($rm E_F$) in UTSn is found to be correlated with the T $d$ PES spectra that have a very low density of states (DOS) near $rm E_F$. The high-resolution PES spectra for UTSn provide the V-shaped reduced metallic DOS near $rm E_F$ but do not reveal any appreciable changes in their electronic structures across the magnetic phase transitions. A possible origin for the reduced N$_f$($rm E_F$) in UTSn is ascribed to the hybridization to the very low T $d$ DOS at $rm E_F$. Comparison of the measured PES spectra to the LSDA+$U$ band structure calculation reveals a reasonably good agreement for UPdSn, but not so for UNiSn.
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