Observation of a spin-textured nematic Kondo lattice

The Kondo lattice model, as one of the most fundamental models in condensed matter physics, has been employed to describe a wide range of quantum materials. Discovering new phases on the Kondo lattice and unveiling their mechanisms are crucial to the understanding of strongly correlated systems. Here, in a layered Kondo magnet USbTe, we observe a spin-textured nematic state and visualize a heavy electronic liquid-crystal phase. Employing scanning tunneling microscopy and spectroscopy (STM/STS), we visualize a tetragonal symmetry breaking of heavy electronic states around the Fermi level, which coincides with the formation of heavy quasi-particles driven by band hybridization. Remarkably, using spin-polarized STM, we demonstrate that the nematic state is spin-polarized, which not only suggests its intrinsically electronic nature but also represents the unique magnetic texture of nematic heavy fermions. Our findings unveil a novel correlation-mediated order whose mechanism is inherently tied to Kondo-lattice physics. The observation of heavy nematic states enriches the phase diagram of correlated systems and provides a rare platform to explore the interplay of Kondo physics, spontaneous symmetry breaking, and quantum criticality. The authors study the layered Kondo magnet USbTe by spin-polarized scanning tunneling microscopy and spectroscopy. They discover a spin-polarized nematic state below 15 K, coinciding with the formation of heavy quasi-particles driven by band hybridization.