Fig. 1From: Breaking the Symmetry of a Metal–Insulator–Metal-Based Resonator for Sensing ApplicationsTop view of the investigated plasmonic sensors, consisting of a MIM bus waveguide coupled with one circular ring-shaped cavity. a case 1: without an inner core, b case 2: with an inner core, and c case 3: with an air path in the inner core, respectivelyBack to article page