Towards a new clock laser system using a ceramic cavity and laser linewidth transfer technique

We propose employing an ultra-low thermal expansion ceramic for long cavity spacers that can reduce thermal noise effect on ultra-stable optical cavities relatively, since the high-rigidity ceramic should be insensitive to vibration. Thermal expansion properties are investigated using a prototype ceramic cavity. Simulation results show that responses of a long ceramic cavity to the vertical acceleration are similar to that of a short ultra-low expansion (ULE) glass cavity. Linewidth transfer technique based on an optical frequency comb combining with the narrow linewidth laser stabilized to the ceramic cavity would serve as a useful ultra-stable local oscillator for optical clocks.