Spatially defined Rabi spectroscopy for uninterrupted optical clock interrogation

Area of Science:

• Atomic physics
• Metrology
• Quantum optics

Background:

• Optical lattice clocks offer high precision but are limited by dead time between atomic state preparation and interrogation.
• Dead time introduces noise (Dick effect) and prevents continuous phase accumulation, hindering clock stability.

Purpose of the Study:

• To demonstrate a novel method for dead-time-free interrogation in optical lattice clocks.
• To improve the stability and precision of atomic clocks by enabling continuous operation.

Main Methods:

• Utilized ultracold strontium-88 atoms continuously transported in a moving optical lattice.
• Implemented spatially defined Rabi spectroscopy using a localized excitation region defined by a transverse magnetic field.
• Employed a longitudinal excitation geometry to preserve Lamb-Dicke confinement and minimize Doppler broadening.

Main Results:

• Achieved a 1.2-Hz-wide spectrum near the transit-time Fourier limit with continuous atom delivery at 16 mm/s.
• Successfully decoupled interrogation from preparation and detection, enabling dead-time-free operation.
• Demonstrated a practical approach to overcome dead-time limitations in optical atomic clocks.

Conclusions:

• Spatially defined interrogation in continuously transported atomic ensembles offers a viable path to dead-time-free optical clocks.
• This method significantly enhances clock stability and precision by allowing continuous phase accumulation.
• The demonstrated technique paves the way for next-generation, highly stable optical atomic clocks.