Breaking Rules but Not Waves: Plasmons in Correlated Materials - CleanTechnica

A recent study led by researchers from the National Renewable Energy Laboratory (NREL) and collaborators worldwide has revealed that hybrid plasmon-polaritons (HPPs)—waves formed by the coupling of plasmons and light—can persist for an exceptionally long time in strongly correlated materials known as "bad" metals. These materials, characterized by intense electron interactions and incoherent electron motion, were previously thought to be unfavorable for sustaining such collective charge waves. The team focused on molybdenum dichloride dioxide (MoOCl2), a bad metal where electron behavior is chaotic, and discovered that HPPs remain stable and propagate effectively even at room temperature, surviving for up to 10 oscillation cycles—longer than in any known crystal. This finding challenges conventional understanding by demonstrating that coherent plasmonic excitations can exist in systems with high resistance and electron incoherence. The research utilized advanced imaging techniques and theoretical models to explain the dielectric response responsible for plasmon creation and longevity. Unlike