Preliminary Investigation of a Calcium Thermal Beam in Order to Build an Operational Optical Clock

Despite the remarkable progress in optical frequency standards over the past decade, the path toward continuously operating optical clocks remains challenging. We are investigating the prospect of achieving good long-term stability with a thermal atomic beam, a straightforward architecture conducive to operational applications. We have demonstrated Ramsey-Borde spectroscopy [1] in calcium down to a full-width of 15 kHz, and we discuss our experimental approach, the status of our work, and our plans for improvement.