Computation of Electromagnetic Whispering Gallery Mode Field in a Dielectric Microring Fabricated on a Metal Wire

Closed-form formulas to calculate electromagnetic whispering gallery mode laser fields in a circular microring are developed. Such a microring is typically made from an optically active polymer, which is fabricated on a metallic wire. Because of the operation frequency, the microring is modeled as an infinite dielectric cylinder with a metallic inner boundary. Vector potential Green functions, from which the whispering gallery mode fields are computed, are presented, and a simplified method of computing fields is introduced. Computed results show that the whispering gallery mode field in the dielectric cylinder is detached from its inner boundary and the phenomena can be achieved by increasing the thickness of the dielectric layer.