Accelerating the averaging rate of atomic ensemble clock stability using atomic phase lock

作者：Shiga Nobuyasu^*; Mizuno Michiaki; Kido Kohta; Phoonthong Piyaphat; Okada Kunihiro

来源：New Journal of Physics, 2014, 16(7): 073029.

DOI：10.1088/1367-2630/16/7/073029

• atomic clocks
• ion trap
• frequency standards

We experimentally demonstrated that the stability of an atomic clock improves at its fastest rate tau(-1) (where tau is the averaging time) when the phase of a local oscillator is genuinely compared to the continuous phase of many atoms in a single trap (an atomic phase lock). For this demonstration, we developed a simple method that repeatedly monitors the atomic phase while retaining its coherence by observing only a portion of the whole ion cloud. Using this new method, we measured the continuous phase over three measurement cycles, and thereby improved the stability scaling from tau(-1/2) to tau(-1) during the three measurement cycles. This simple method provides a path by which atomic clocks can approach a quantum projection noise limit, even when the measurement noise is dominated by the technical noise.

• 出版日期2014-7-22