Surface-mediated ultra-strong cavity coupling of two-dimensional itinerant electrons

• DOI: 10.48550/arxiv.2409.10615
• Publication Date: 2024-09-16
• Authors: Christian Eckhardt; Andrey Grankin; Dante M. Kennes; Michael Ruggenthaler; Ángel Rubio; Michael A. Sentef; Mohammad Hafezi; Marios H. Michael
• Keywords: Condensed Matter - Strongly Correlated Electrons; Quantum Physics; Strongly Correlated Electrons (cond-mat.str-el); FOS: Physical sciences; Quantum Physics (quant-ph)

Engineering phases of matter in cavities requires effective light-matter coupling strengths that are on the same order magnitude as bare system energetics, coined ultra-strong regime. For models itinerant electron systems, which do not have discrete energy levels, a clear definition this regime is outstanding to date. Here we argue change electronic mass exceeding $10\%$ its value may serve such definition. We propose quantitative computational scheme for obtaining relation vacuum and show surface polariton modes can induce changes. Our results important implications cavity design principles enable engineering properties with quantum light.