Tuning the Charge Density Wave and Low-Energy Magnetic States with Nanoscale Strains in GdTe₃

Abstract Recent advances in strain engineering have enabled unprecedented control over quantum states in strongly correlated magnetic systems. However, nanoscale strain modulation of charge density waves (CDWs) and magnetically excited states, which is crucial for atomically precise strain engineering and practical spintronic applications, remains unexplored. Here, we report the nanoscale strain effects on CDWs and low-energy electronic states in the van der Waals antiferromagnetic metal GdTe₃, utilizing scanning tunneling microscopy/spectroscopy. Low-temperature cleavage introduces local strains, resulting in the formation of nanoscale wrinkles on the GdTe₃ surface. Atomic displacement analysis reveals two distinct types of wrinkles: Wrinkle-I, originating from unidirectional strain, and Wrinkle-II, dominated by shear strain. In Wrinkle-I, the tensile strain enhances the CDW gap, while the compressive strain induces a single low-energy magnetic state. Wrinkle-II switches the orientation of CDW, leading to the formation of an associated CDW domain wall. In addition, three low-energy magnetic states that exhibit magnetic field-dependent shifts and intensity variations emerge within the CDW gap around Wrinkle-II, indicative of a strain-tuned coupling between CDW order and localized 4f-electron magnetism. These findings establish nanoscale strain as a powerful tuning knob for manipulating intertwined electronic and magnetic excitations in correlated magnetic systems.