Direct Generation of Tailored Pulse-Mode Entanglement

Area of Science:

• Quantum Information Science
• Quantum Optics
• Photonics

Background:

• Photonic quantum technology increasingly relies on frequency encoding for enhanced information density and noise resilience.
• Pulsed time-frequency modes (TFM) offer a unique spectral encoding for quantum states, enabling comprehensive quantum information processing.
• Efficient generation of high-fidelity entangled TFM states is crucial for advancing quantum protocols.

Purpose of the Study:

• To demonstrate a novel technique for the direct generation of entangled TFM-encoded states.
• To achieve high rates, heralding efficiency, and state fidelity in TFM state generation.
• To showcase the utility of these states in a four-photon entanglement swapping scheme.

Main Methods:

• Utilized single-pass, tailored down-conversion processes for direct TFM state generation.
• Characterized state quality using highly resolved time-of-flight fiber spectroscopy.
• Verified entanglement and fidelity through two-photon interference measurements.

Main Results:

• Successfully generated entangled TFM-encoded states with unprecedented quality.
• Achieved high generation rates, excellent heralding efficiency, and high state fidelity.
• Demonstrated the applicability of the generated states in a four-photon entanglement swapping protocol.

Conclusions:

• The developed technique provides a direct and efficient method for generating high-quality entangled TFM states.
• This advancement is a significant step towards practical TFM-encoded quantum information processing.
• The generated states serve as a valuable primitive for complex quantum protocols and future quantum networks.