New possibilities for frequency standards using laser cooling and detection of stored ions

Techniques for storing 10⁴ to 10⁵ ions for periods of hours to days are described in detail. Ion dynamics and detection techniques are also covered. Experimental data is presented demonstrating that ions stored in a room temperature Penning style ion trap using dc electric and magnetic fields can be coolteod near ZERO Kelvin using a suitable laser. This cooling technique, which is appliciable to very many atomic and molecular ions, can reduce fractional frequency shifts due to the second order Doppler effetc to smaller than 10^-15. This cooling, coupled with the other attractive features of ion storage, promises to make possible frequency standards with stabilities in the 10^-16 to 10^-18 range with accuracies of order 10^-15 or better. One possible candidate for a microwave frequency standard is described.