Controlled multi-photon subtraction with cascaded Rydberg superatoms as single-photon absorbers.

Area of Science:

• Quantum optics
• Atomic physics
• Photonics

Background:

• Precise control of individual photons is crucial for quantum information processing.
• Existing methods for photon manipulation often lack scalability and exactness.

Purpose of the Study:

• To demonstrate exact and controlled multi-photon subtraction from light pulses.
• To explore the use of cold atom ensembles for quantum optical operations.

Main Methods:

• Utilizing a cascaded system of cold atom ensembles.
• Employing strong, collectively enhanced coupling of photons to Rydberg states.
• Leveraging Rydberg blockade for single-photon absorption per ensemble.

Main Results:

• Experimentally demonstrated controlled multi-photon subtraction with up to three absorbers.
• Identified weak Raman decay as the primary source of infidelity.
• Investigated the performance limitations due to Raman decay.

Conclusions:

• The developed system offers a novel approach for precise photon subtraction.
• The findings pave the way for enhanced quantum light sources and photonic devices.
• Understanding infidelity sources is critical for future improvements.