Influence of high-frequency laser frequency noise on the stability of an optical clock

Neutral atom optical frequency standards have the potential to reach extremely high stabilities due to a high number of atoms. The frequency noise of the interrogation laser can lead to a significant degradation of the stability of a frequency standard through aliasing (Dick effect). Thus, to exploit the potential of the frequency standards, the spectral density of the frequency noise of the laser must be sufficiently low. In this paper we discuss the influence of the high-frequency noise in an optical clock based on ultracold calcium atoms and show how the high-frequency laser frequency noise can be efficiently suppressed by using the reference optical cavity as a filter.