Entanglement-preserving frequency conversion in cold atoms

Abstract

We propose a method that enables efficient frequency conversion of quantum information based on recently demonstrated strong parametric coupling between two single-photon pulses propagating in a slow-light atomic medium at different group velocities. We show that an incoming single-photon state is efficiently converted into another optical mode in a lossless and shape-conserving manner. The persistence of initial quantum coherence and entanglement within frequency conversion is also demonstrated. We first illustrate this result for the case of small frequency difference of converted photons, and then discuss the modified scheme for conversion of photon wavelengths in different spectral ranges. Finally we analyze the generation of a narrow-band single-photon frequency-entangled state.

minor corrections compared to the published version, 7 pages, 5 figures

References in corpus (2)

• Deterministic single photons via conditional quantum evolution
• Creation of a Photonic Time-bin Qubit via Parametric Interaction of Photons in a Driven Resonant Medium

Cited by in corpus (7)

• Coherent conversion between microwave and optical photons -- an overview of physical implementations
• Efficiency of light-frequency conversion in an atomic ensemble
• Dressed-state electromagnetically induced transparency for light storage in uniform phase spin-waves
• Quantum Repeaters based on Deterministic Storage of a Single Photon in distant Atomic Ensembles
• Qubit transfer between photons at telecom and visible wavelengths in a slow-light atomic medium
• Single-photon frequency conversion in nonlinear crystals
• Entanglement transfer during quantum frequency conversion in gas-filled hollow-core fibers