Ultra-stable optical cavity design for low vibration sensitivity

We present the details of two different designs of ultra stable optical cavity for laser stabilization; one with vertical optical axis geometry, the other horizontal. Finite Element Modelling analysis is used to predict and subsequently decrease the influence of vibrations on these stabilized laser cavities. Analysis of the horizontal cavity includes full consideration of the effect of mirror tilt under horizontal acceleration. The cavities are constructed, using fused silica mirrors to decrease the thermal noise limit while maintaining good midterm stability. Vibration sensitivity components measured are equal to or better than 1.5e-11/(m.s^-2) for each spatial direction. Relative frequency measurements show that at least one of the cavities has a stability better than ~5.6e-16 at 1s.