Moir\'e-mediated phases in synthetic Kondo superlattices

Jyotirish Das; Onur Erten

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arXiv · 2408.05324

Moir\'e-mediated phases in synthetic Kondo superlattices

Jyotirish Das·Onur Erten

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Abstract

Motivated by the recent experiments on van der Waals heterostructures involving metallic and Mott insulating layers, we construct a moir\'e extension of the Kondo-Heisenberg model and study its phase diagram via Abrikosov fermion mean field theory in one and two dimensions. Our analysis indicates that the stacking dependent Kondo interaction can lead to a variety of new phases. In particular, we show that magnetic order and heavy quasiparticles can nucleate at different regions in the moir\'e unit cell leading to a macroscopic real space phase separation. We observe that these factors can lead to a metal to Kondo insulator percolation transition in two dimensions. Our results highlight the rich physics that can arise in moir\'e superlattices that are composed of inherently strongly correlated layers.

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Jyotirish Das, Onur Erten. 2024-08-09. Moir\'e-mediated phases in synthetic Kondo superlattices. https://arxiv.org/abs/2408.05324

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