Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Accelerating the Averaging Rate of Atomic Ensemble Clock Stability using
  Atomic Phase Lock   We experimentally demonstrated that the stability of an atomic clock improves
at 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 (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 3 measurement
cycles, and thereby improved the stability scaling from $\tau^{-1/2}$ to
$\tau^{-1}$ during the 3 measurement cycles.
  %Compared with the standard method that initialize phase during each
measurement cycle, the long term stability was improved by a factor of
$\sqrt{n_{cp}}$ (where $n_{cp}$ is the number of continuous phase
measurements).
  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.

5
The categories of this paper are: gr-qc
34
The categories of this paper are: chem-ph
6
The categories of this paper are: astro-ph
25
The categories of this paper are: patt-sol
1
The categories of this paper are: cs
4
The categories of this paper are: cond-mat
31
The categories of this paper are: ao-sci
15
The categories of this paper are: nucl-ex
36
The categories of this paper are: cmp-lg
22
The categories of this paper are: chao-dyn
12
The categories of this paper are: nucl-th
21
The categories of this paper are: adap-org
9
The categories of this paper are: nlin
35
The categories of this paper are: mtrl-th
11
The categories of this paper are: hep-lat
24
The categories of this paper are: dg-ga