From Dyakonov-Cherenkov radiation to Dyakonov surface optics

Cherenkov radiation by swift charged particles in a dielectric medium has been used for a long time as an effective means for particle detection and measurements of their energy 1 , 2 , 3 , 4 , 5 . Now a team led by Prof. Yu Luo from Singapore considers a situation when the particle emits surface electromagnetic waves at the interface between an isotropic and a uniaxial-birefringent medium (Dyakonov surface waves 6 ). The resulting Dyakonov-Cherenkov radiation is shown to be highly sensitive to both the value and the direction of the particle velocity 7 . In particular, it is shown that close to the Cherenkov threshold, the radiation intensity can be several orders of magnitude greater than that in traditional Cherenkov detectors. These new features allow to determine simultaneously the magnitude and direction of particle velocities on a compact platform (Fig. 1 ). Fig. 1: Surface Dyakonov-Cherenkov radiation. a Schematics of surface Dyakonov-Cherenkov radiation. A swift charged particle moving in a structure made of semi-infinite isotropic and birefringent material excites Dyakonov surface waves, leading to surface Dyakonov-Cherenkov radiation. b Radiation pattern of surface Dyakonov-Cherenkov radiation. (Reproduced with permission from ref. 7 Copyright 2021, Nature Publishing Group.) Full size image