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Title: Secure self-calibrating quantum random-bit generator

Journal Article · · Physical Review. A
; ; ; ;  [1]
  1. Hewlett-Packard Laboratories, 1501 Page Mill Road MS 1123, Palo Alto, California 94304-1100 (United States)

Random-bit generators (RBGs) are key components of a variety of information processing applications ranging from simulations to cryptography. In particular, cryptographic systems require 'strong' RBGs that produce high-entropy bit sequences, but traditional software pseudo-RBGs have very low entropy content and therefore are relatively weak for cryptography. Hardware RBGs yield entropy from chaotic or quantum physical systems and therefore are expected to exhibit high entropy, but in current implementations their exact entropy content is unknown. Here we report a quantum random-bit generator (QRBG) that harvests entropy by measuring single-photon and entangled two-photon polarization states. We introduce and implement a quantum tomographic method to measure a lower bound on the 'min-entropy' of the system, and we employ this value to distill a truly random-bit sequence. This approach is secure: even if an attacker takes control of the source of optical states, a secure random sequence can be distilled.

OSTI ID:
20982280
Journal Information:
Physical Review. A, Vol. 75, Issue 3; Other Information: DOI: 10.1103/PhysRevA.75.032334; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 1050-2947
Country of Publication:
United States
Language:
English