High-Performance Coherent Population Trapping Clock with Polarization Modulation

The authors use a single laser beam with synchronously modulated polarization and phase to trap atoms in a superposition state, decoupled from the light. Thanks to the linear architecture of this setup, it can serve as a compact, high-performance vapor-cell atomic clock. Such systems based on coherent population trapping are desired as successors to the well-known rubidium clock, particularly for applications in navigation and telecommunication. This setup offers frequencies an order of magnitude more stable than from a typical industrial clock.