Inhomogeneous Kondo-lattice in geometrically frustrated Pr₂Ir₂O₇

Area of Science:

• Condensed Matter Physics
• Quantum Materials Science
• Materials Chemistry

Background:

• Geometric frustration in pyrochlore iridates disrupts long-range magnetic order.
• Pr₂Ir₂O₇ exists at an antiferromagnetic-to-paramagnetic quantum critical point, exhibiting complex phenomena like the Kondo effect and metallic spin liquid behavior.

Purpose of the Study:

• To probe the local electronic states of Pr₂Ir₂O₇ using advanced spectroscopic techniques.
• To understand the interplay between geometric frustration, Kondo entanglement, and electronic phase separation in this quantum critical material.

Main Methods:

• Spectroscopic imaging with scanning tunneling microscopy.
• Integration of machine learning, density functional theory, and theoretical modeling.
• Analysis of nanoscale electronic phase separation and fractal geometry.

Main Results:

• Discovery of nanoscale electronic phase separation in Pr₂Ir₂O₇.
• Identification of distinct regions: one with Kondo resonance and another with Kondo destruction (non-magnetic metallic phase).
• Observation of fractal spatial patterns with power-law behavior, indicative of proximity to a critical point.

Conclusions:

• Pr₂Ir₂O₇ exhibits a complex electronic landscape at the nanoscale due to quantum criticality.
• Spatial electronic potential variations can be used to tune the balance between Kondo entanglement and geometric frustration.
• This work reveals a novel nanoscale tuning route for quantum materials.