The article "Polaritons in van der Waals materials" by D. N. Basov, M. M. Fogler, and F. J. García de Abajo discusses the unique properties and applications of polaritons in van der Waals (vdW) materials. Polaritons are hybrid light-matter modes that arise from the interaction of light and matter, and they exhibit strong confinement and tunability due to the low-dimensional nature of vdW materials. The authors highlight the diverse types of polaritons found in vdW materials, including surface plasmon polaritons, phonon polaritons, exciton polaritons, and Cooper-pair polaritons. These polaritons can be manipulated through various methods such as electrical gating, nanostructuring, and heterostructuring, leading to applications in nano-optics, electro-optical modulators, subdiffractional focusing, optical sensing, and light emission. The article also explores the potential for using polaritons to study fundamental physics, such as quantum phenomena and topological properties, and discusses the challenges and opportunities in realizing these applications.The article "Polaritons in van der Waals materials" by D. N. Basov, M. M. Fogler, and F. J. García de Abajo discusses the unique properties and applications of polaritons in van der Waals (vdW) materials. Polaritons are hybrid light-matter modes that arise from the interaction of light and matter, and they exhibit strong confinement and tunability due to the low-dimensional nature of vdW materials. The authors highlight the diverse types of polaritons found in vdW materials, including surface plasmon polaritons, phonon polaritons, exciton polaritons, and Cooper-pair polaritons. These polaritons can be manipulated through various methods such as electrical gating, nanostructuring, and heterostructuring, leading to applications in nano-optics, electro-optical modulators, subdiffractional focusing, optical sensing, and light emission. The article also explores the potential for using polaritons to study fundamental physics, such as quantum phenomena and topological properties, and discusses the challenges and opportunities in realizing these applications.