Recent progress on cryogenic MASER oscillator

Abstract

This paper reports on the comparison of a Cryocooled Sapphire Oscillator with our Cryocooled MASER Oscillator thanks to a home-made synthesis chain. The MASER oscillator demonstrates for the first time a fractional frequency deviation below 6 · 10−15 over 4 s sampling time which is comparable to the conventional CSRO but achieved in a free running environment.