Autocompensating quantum cryptography

Enhanced autocompensating quantum cryptography system.

We have improved the hardware and software of our autocompensating system for quantum key distribution by replacing bulk optical components at the end stations with fiber-optic equivalents and implementing software that synchronizes end-station activities, communicates basis choices, corrects errors, and performs privacy amplification over a local area network. The all-fiber-optic arrangement p...

One-way entangled-photon autocompensating quantum cryptography

A quantum cryptography implementation is presented that uses entanglement to combine one-way operation with an autocompensating feature that has hitherto only been available in implementations that require the signal to make a round trip between the users. Using the concept of advanced waves, it is shown that this proposed implementation is related to the round-trip implementation in the same w...

Symmetric Autocompensating Quantum Key Distribution

We present quantum key distribution schemes which are autocompensating (require no alignment) and symmetric (Alice and Bob receive photons from a central source) for both polarization and timebin qubits. The primary benefit of the symmetric configuration is that both Alice and Bob may have passive setups (neither Alice nor Bob is required to make active changes for each run of the protocol). We...

One-Way Autocompensating Quantum Cryptography via Auto-Phase-Matched Spontaneous Parametric Down-Conversion

We present a new quantum cryptography implementation that uses frequency-correlated photon pairs to combine one-way operation with an autocompensating feature that has hitherto only been available in implementations that require the signal to make a round trip between the users. Furthermore, we describe a new scheme for creating frequency-correlated photon pairs (auto-phase-matched spontaneous ...

Quantum Cryptography