1999/11/25 by W. Tittel, J. Brendel, H. Zbinden +1
Physics and Astronomy · #quant-ph
paper · pdf · doi:10.1103/physrevlett.84.4737
4 pages including 2 figures
arxiv created 1999/11/25 · arxiv updated 2009/12/01
We present a setup for quantum cryptography based on photon pairs in energy-time Bell states and show its feasability in a laboratory experiment. Our scheme combines the advantages of using photon pairs instead of faint laser pulses and the possibility to preserve energy-time entanglement over long distances. Moreover, using 4-dimensional energy-time states, no fast random change of bases is required in our setup : Nature itself decides whether to measure in the energy or in the time base.