Frequency-Stability Performances of the Pulsed Optically Pumped Rubidium Clock: Recent Results and Future Perspectives

Abstract

<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> This paper presents new results obtained with a laboratory prototype of a pulsed optically pumped frequency standard based on a vapor cell containing <formula formulatype="inline"><tex>$^{87}\hbox{Rb}$</tex></formula> diluted in a buffer gas. A frequency stability of about <formula formulatype="inline"><tex>$1.2 \times 10^{-12}$ </tex></formula> <formula formulatype="inline"><tex>$\tau^{-1/2}$</tex></formula> has been measured, and the value of <formula formulatype="inline"><tex>$3 \times 10^{-15}$</tex></formula> for integration times of <formula formulatype="inline"><tex>$10^{5}$</tex></formula> s has been achieved (drift removed data). These performances show that a suitable implementation of this standard can lead to a compact vapor-cell clock with a very interesting short- and medium-term frequency stability and, consequently, may be of great interest in radio-navigation systems. We also present some possible improvements of the pulsed technique. </para>