Authors: Hai Hu, Na Chen, Hanchao Teng, Renwen Yu, Mengfei Xue, Ke Chen, Yuchuan Xiao, Yunpeng Qu, Debo Hu, Jianing Chen, Zhipei Sun, Peining Li, F. Javier García de Abajo, Qing Dai
Published: 2023-03-31
Source: Full article
Negative refraction provides a platform to manipulate mid-infrared and terahertz radiation for molecular sensing and thermal emission applications. However, its implementation based on metamaterials and plasmonic media presents challenges with optical losses, limited spatial confinement, and lack of active tunability in this spectral range. We demonstrate gate-tunable negative refraction at mid-infrared frequencies using hybrid topological polaritons in van der Waals heterostructures. Specifically, we visualize wide-angle negatively refracted polaritons in α-MoO