Development of a miniature laser-cooled Cs fountain frequency standard at NIST

We are developing a small laser-cooled Cs fountain at NIST with the goal of achieving exceptional short-term stability of σ_y (τ)≈2×10^-14τ^-1/2 with a long-term stability of ≈10^-15. Although this device is not designed to achieve the accuracy of the NIST primary frequency standard NIST-F1, this small, portable system will prove valuable as a local oscillator with intermediate accuracy. We discuss the performance goals of this frequency standard, the design philosophy, the existing physics package, and future directions