High-Rate Field Demonstration of Large-Alphabet Quantum Key Distribution
Abstract
Quantum key distribution (QKD) enables secure symmetric key exchange for information-theoretically secure communication via one-time-pad encryption. QKD also enables frequent re-keying of symmetric block ciphers. A goal for QKD in both settings is to increase the secret-key generation rate. In metro-scale links, the detectors limit the rates attainable by single-photon-based QKD schemes: the long reset time (compared to the detection timing jitter) of even advanced single-photon detector technologies caps the maximum secret-key rate for binary-encoded systems below what the optical channel could support. For a given detector technology, this cap can be raised by encoding photons in high-dimensional basis states (qudits instead of qubits), so that each detected photon yields more information than would be possible under binary encoding [3]. Here, we demonstrate a record QKD rate for three different channel losses using a new prepare-and-measure high-speed, large-alphabet QKD protocol, including the firstfield demonstration of large-alphabet QKD.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 12, 2016
- Accession Number
- AD1032250
Entities
People
- Benjamin P. Dixon
- Catherine Lee
- Darius Bunandar
- Dirk Englund
- Gregory R. Steinbrecher
- Jeffrey H Shapiro
- Scott A. Hamilton
- Wong N. Wong
- Zheshen Zhang
Organizations
- Massachusetts Institute of Technology