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arXiv · 2512.24668

Disentangle Intertwined Interactions in Correlated Charge Density Wave with Magnetic Impurities

J. W. Park·H. Kim·H. W. Yeom
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Abstract

Magnetic impurities in strongly correlated electronic systems serve as sensitive probes to a wide range of many-body quantum phenomena. Broken symmetries in such a system can lead to inequivalent lattice sites, and magnetic impurities may interact selectively with particular orbitals or sublattices. However, the microscopic mechanisms behind such site-specific interactions have been poorly understood. Here, we explore the behavior of individual Fe adatoms on a cluster-Mott charge-density-wave (CDW) system of 1T-TaS2 utilizing scanning tunneling microscopy/spectroscopy (STM/STS) and density functional theory (DFT). Our measurements uncover pronounced site-dependent electronic states of CDW clusters with Fe adatoms, indicating distinct local coupling to cluster-Mott states. DFT calculations identify three distinct types of interactions; hybridization with localized correlated electrons, distorting the CDW cluster, and charge transfer. In particular, the hybridization of Fe 3d and half-filled Ta 5dz2 orbitals suppresses the Mott insulating state for an adatom at the center of a CDW cluster. While the results underscore a crucial role of the direct orbital hybridization and the limitation of the prevailing single-site Kondo impurity model, they suggest the possibility of controlling entangled interactions separately in a cluster Mott insulator.

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J. W. Park, H. Kim, H. W. Yeom. 2025-12-31. Disentangle Intertwined Interactions in Correlated Charge Density Wave with Magnetic Impurities. https://arxiv.org/abs/2512.24668

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