Frequency-temperature compensation in Ti/sup 3+/ and Ti/sup 4+/ doped sapphire whispering gallery mode resonators

A new method of compensating the frequency-temperature dependence of high-and monolithic sapphire dielectric resonators near liquid nitrogen temperature is presented. This is achieved by doping monocrystalline sapphire with Ti/sup 3+/ ions. This technique offers significant advantages over other methods.