Isotropic Absorption and Sensor of Vertical Split‐Ring Resonator

Four vertical split-ring resonators with a significant plasmon confinement for an isotropic perfect absorption are demonstrated. The polarization-insensitive absorption can be kept at a high value even when the angle of incidence is larger than 60°. A refractive index sensor with high sensing performance is also proposed because of its high absorption ability. As a service to our authors and readers, this journal provides supporting information supplied by the authors. Such materials are peer reviewed and may be re-organized for online delivery, but are not copy-edited or typeset. Technical support issues arising from supporting information (other than missing files) should be addressed to the authors. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.