Stealthy hyperuniform disorder: A new route to controlling electric states and magnetic phase transition in correlated systems

Akihisa Koga; Takanori Sugimoto

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arXiv · 2604.19041

Stealthy hyperuniform disorder: A new route to controlling electric states and magnetic phase transition in correlated systems

Akihisa Koga·Takanori Sugimoto

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Abstract

We investigate the effects of stealthy hyperuniform bond distributions on the electronic and magnetic properties of the Hubbard model on the honeycomb lattice. Hyperuniform structures, distinct from random and quasiperiodic ones, have recently attracted considerable interest due to their anomalous suppression of density fluctuations. By diagonalizing the noninteracting Hamiltonian, we show that a linear density of states (DOS) robustly emerges, while the stealth property of the bond distribution changes the wave functions in the higher-energy region extended and significantly modifies the DOS near the band edge. To clarify the impact on magnetism, we apply the real-space Hartree approximation to the Hubbard model. We find that, the phase transition always occurs between semimetallic and antiferromagnetically ordered states and its critical interaction strength is sensitive to the stealth property. A comparison with the quasiperiodic honeycomb tiling further highlights the role of structural correlations. These results demonstrate that stealthy hyperuniform disorder provides a novel route to controlling electronic states and magnetic phase transitions in correlated systems.

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Akihisa Koga, Takanori Sugimoto. 2026-04-21. Stealthy hyperuniform disorder: A new route to controlling electric states and magnetic phase transition in correlated systems. https://arxiv.org/abs/2604.19041

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