Reading the phase of a Raman excitation with a multi-state atomic interferometer

Area of Science:

• Quantum Information Science
• Atomic Physics
• Quantum Optics

Background:

• Atomic memories are vital for quantum repeaters and photonic qubit applications.
• Coherent information transfer from light to atomic states is typically verified optically.
• Direct detection of atomic coherence offers a new verification pathway.

Purpose of the Study:

• To report the direct detection of atomic coherence using atom interferometry.
• To verify the coherent transfer of quantum information to atomic states.
• To demonstrate controllable phase imprinting and recovery on atomic coherence.

Main Methods:

• Utilizing atom interferometry for direct detection of atomic coherence.
• Employing a bichromatic laser field to close a Raman transition.
• Experimentally verifying phase imprinting and recovery after variable time delays.

Main Results:

• Direct detection of atomic coherence was achieved via atom interferometry.
• A bichromatic laser field was shown to imprint a distinct, controllable phase on atomic coherence.
• Atomic coherence was successfully recovered after a variable time delay.

Conclusions:

• Atom interferometry provides a direct method for verifying atomic coherence in quantum memory applications.
• The demonstrated technique allows for precise control and recovery of quantum information stored in atomic states.
• This advancement is significant for the development of quantum repeaters and other quantum technologies.