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Angle-resolved photoemission spectroscopy study of crystal electric field in heavy fermion compound CePt2In7

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 نشر من قبل Jian-Qiao Meng
 تاريخ النشر 2019
  مجال البحث فيزياء
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The three-dimensional electronic structure and Ce 4f electrons of the heavy fermion superconductor CePt2In7 is investigated. Angle-resolved photoemission spectroscopy using variable photon energy establishes the existence of quasi-two and three dimensional Fermi surface topologies. Temperature-dependent 4d-4f on-resonance photoemission spectroscopies reveal that heavy quasiparticle bands begin to form at a temperature well above the characteristic (coherence) temperature T*. T* emergence may be closely related to crystal electric field splitting, particularly the low-lying heavy band formed by crystal electric field splitting.



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