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Title: Self-referenced continuous-variable quantum key distribution protocol

We introduce a new continuous-variable quantum key distribution (CV-QKD) protocol, self-referenced CV-QKD, that eliminates the need for transmission of a high-power local oscillator between the communicating parties. In this protocol, each signal pulse is accompanied by a reference pulse (or a pair of twin reference pulses), used to align Alice’s and Bob’s measurement bases. The method of phase estimation and compensation based on the reference pulse measurement can be viewed as a quantum analog of intradyne detection used in classical coherent communication, which extracts the phase information from the modulated signal. We present a proof-of-principle, fiber-based experimental demonstration of the protocol and quantify the expected secret key rates by expressing them in terms of experimental parameters. Our analysis of the secret key rate fully takes into account the inherent uncertainty associated with the quantum nature of the reference pulse(s) and quantifies the limit at which the theoretical key rate approaches that of the respective conventional protocol that requires local oscillator transmission. The self-referenced protocol greatly simplifies the hardware required for CV-QKD, especially for potential integrated photonics implementations of transmitters and receivers, with minimum sacrifice of performance. Furthermore, it provides a pathway towards scalable integrated CV-QKD transceivers, a vital step towardsmore » large-scale QKD networks.« less
 [1] ;  [2] ;  [2] ;  [3] ;  [3] ;  [4] ;  [4]
  1. Sandia National Lab. (SNL-CA), Livermore, CA (United States); Stanford Univ., Stanford, CA (United States)
  2. Sandia National Lab. (SNL-CA), Livermore, CA (United States)
  3. Univ. of Waterloo, Waterloo, ON (Canada)
  4. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Publication Date:
Report Number(s):
SAND-2015-1631J; SAND-2016-4258J
Journal ID: ISSN 2160-3308; PRXHAE; 567429
Grant/Contract Number:
Published Article
Journal Name:
Physical Review. X
Additional Journal Information:
Journal Volume: 5; Journal Issue: 4; Journal ID: ISSN 2160-3308
American Physical Society
Research Org:
Sandia National Lab. (SNL-CA), Livermore, CA (United States); Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Sponsoring Org:
USDOE National Nuclear Security Administration (NNSA)
Country of Publication:
United States
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; optics; quantum physics; quantum information
OSTI Identifier:
Alternate Identifier(s):
OSTI ID: 1236226; OSTI ID: 1257817