Orbital-Selective Kondo Entanglement and Antiferromagnetic Order in USb_{2}

Area of Science:

• Condensed Matter Physics
• Materials Science
• Quantum Materials

Background:

• Heavy-fermion compounds exhibit exotic properties due to the dual nature of f electrons.
• Actinide materials, particularly those with 5f electrons, are crucial for understanding the interplay between magnetic order and Kondo entanglement in correlated electron systems.

Purpose of the Study:

• To investigate the electronic structure of USb2 in its antiferromagnetic state.
• To elucidate the competition between magnetic order and Kondo entanglement in strongly correlated f-electron systems.

Main Methods:

• Angle-resolved photoemission spectroscopy (ARPES) was employed to determine the electronic structure.
• Polarization-dependent and temperature-dependent ARPES measurements were utilized to distinguish orbital characters and correlation effects.

Main Results:

• Two distinct types of nearly flat bands were observed in the antiferromagnetic state of USb2.
• Polarization-dependent measurements confirmed these bands originate from 5f orbitals with different characters.
• Temperature-dependent measurements revealed one band is driven by Kondo correlations, while the other reflects magnetic order.

Conclusions:

• Orbital selectivity plays a significant role in the competition between Kondo correlations and magnetic order in USb2.
• These findings offer new insights into the rich quantum phases of strongly correlated f-electron systems.