Femtosecond Time-Bin Entangled Qubits for Quantum Communication

  title={Femtosecond Time-Bin Entangled Qubits for Quantum Communication},
  author={Ivan Marcikic and Hugues de Riedmatten and Wolfgang Tittel and Valerio Scarani and Hugo Zbinden and Nicolas Gisin},
We create pairs of non-degenerate time-bin entangled photons at telecom wavelengths with ultrashort pump pulses. Entanglement is shown by performing Bell kind tests of the Franson type with visibilities of up to 91 %. As time-bin entanglement can easily be protected from decoherence as encountered in optical fibers, this experiment opens the road for complex quantum communication protocols over long distances. We also investigate the creation of more than one photon pair in a laser pulse and… 

Figures from this paper

Simultaneous type-I and type-II phase matching for second-order nonlinearity in integrated lithium niobate waveguide.

It is demonstrated that phase matching for both type-I and type-II second-order optical nonlinearity can be realized simultaneously in the same waveguide fabricated from thin-film lithium niobate.

Basics of quantum communication

Entanglement distribution in multi-platform buffered-router-assisted frequency-multiplexed automated repeater chains

The inclusion of a quantum buffer structure between repeaters and routers is shown to improve the achievable entanglement distribution rates in the network and is compatible with the proposed architecture through the inclusion of an extra layer of temporal multiplexing in the QR’s operation.

Adaptable transmitter for discrete and continuous variable quantum key distribution.

A versatile transmitter capable of performing both discrete variable and continuous variable quantum key distribution protocols (DV-QKD and CV-QkD) is presented, suitable for re-configurable optical networks where the QKD protocol is selected to optimize the performance according to the parameters of the links.

Integrated photonics on thin-film lithium niobate

From basic principles to the state of the art—the diverse aspects of integrated thin-film LN photonics, including the materials, basic passive components, and various active devices based on electro-optics, all-optical nonlinearities, and acousto- optics are covered.

Feasible time-bin entanglement purification based on sum-frequency generation.

This paper presents the first entanglement purification protocol (EPP) for time-bin entangled state, which does not require the sophisticated controlled-not (CNOT) gate or similar operations, and it uses the feasible sum-frequency generation (SFG) to perform the purification.

SeQUeNCe: a customizable discrete-event simulator of quantum networks

This work develops SeQUeNCe, a comprehensive, customizable quantum network simulator, which is designed to enable comparisons of alternative quantum network technologies, experiment planning, and validation and to aid with new protocol design.

Entangled photon-pair sources based on three-wave mixing in bulk crystals.

This manuscript provides a review of the state-of-the-art bulk-optics-based SPDC sources with continuous wave pump and discusses some of the main considerations when building for deployment.

Bell correlations between light and vibration at ambient conditions.

This work presents a scheme leveraging universal properties of spontaneous Raman scattering to demonstrate Bell correlations between light and a collective molecular vibration, and measures the decay of these hybrid photon-phonon Bell correlations with sub-picosecond time resolution.

Toward Practical Quantum Secure Direct Communication: A Quantum-Memory-Free Protocol and Code Design

It is demonstrated that the QMF-DL04 QSDC scheme significantly increases both the secure information rate and the communication distance of the original DL04 protocol, and significantly improves the originalDL04QSDC’s robustness.