We present a scheme to encode M extra classical bits to a dense-coded pair of photons. By tuning the delay of an entangled pair of photons to one of 2^M time-bins and then applying one of the quantum dense coding protocols, a receiver equipped with a synchronized clock of reference is able to decode M bits (via classical time-bin encoding) + 2 bits (via quantum dense coding). This protocol, yet simple, does not dispense several special features of the used programmable delay apparatus to maintain the coherence of the two-photon state. While this type of time-domain encoding may be thought to be ideally of boundless photonic capacity (by increasing the number of available time-bins), errors due to the environmental noise and the imperfect devices and channel evolve with the number of time-bins.

Date Published: 29 April 2016
PDF: 7 pages
Proc. SPIE 9900, Quantum Optics, 99000L (29 April 2016); doi: 10.1117/12.2227482

Published in SPIE Proceedings Vol. 9900:
Quantum Optics
Jürgen Stuhler; Andrew J. Shields, Editor(s)