Strong Coupling between Whispering Gallery Modes and Chromium Ions in Ruby

Warrick G. Farr, Maxim Goryachev, Daniel L. Creedon +1

We report the study of interactions between cavity photons and paramagnetic Cr${}^{3+}$ spins in a ruby (Cr${}^{3+}$:Al${}_2$O${}_3$) Whispering Gallery mode (WGM) resonator. Examining the…