We describe the operation of a laser cooled cesium fountain clock in the quantum limited
regime. An ultrastable cryogenic sapphire oscillator is used to measure the short-term …

We give an overview of the work done with the Laboratoire National de Metrologie et
d'Essais-Systemes de Reference Temps-Espace (LNE-SYRTE) fountain ensemble during …

Atomic frequency standards using trapped ions or cold atoms work intrinsically in a pulsed
mode. Theoretically and experimentally, this mode of operation has been shown to lead to a …

The stability and accuracy of atomic microwave frequency standards (atomic clocks) have
been improving at a rate exceeding one order of magnitude per decade for the past 30 …

This volume is a comprehensive introduction to the physics of time and time measurement,
from an historical perspective to the modern day. It discusses the stability and accuracy of …

We describe the operation of a laser-cooled rubidium 87 Rb frequency standard. We present
a new measurement of the 87 Rb hyperfine frequency with a 1.3× 10− 14 relative accuracy …

This paper reviews recent progress on microwave clocks using laser cooled neutral atoms.
With an ultra-stable cryogenic sapphire oscillator as interrogation oscillator, a cesium …

For more than four decades, caesium atomic clocks have been the backbone in a variety of
demanding applications in science and technology. Neither satellite based navigation …

We demonstrate a laser system with a frequency instability of 0.7 Hz for integration times of
20 s, corresponding to 2.3× 10− 15 fractional instability. This is the lowest short-term …

We review the techniques used in the design and construction of cryogenic sapphire
oscillators at the University of Western Australia over the 18 year history of the project. We …