Quantum cryptography using femtosecond-pulsed parametric down-conversion

A. V. Sergienko, M. Atature, Z. Walton, G. Jaeger, B. E. A. Saleh, and M. C. Teich Quantum Imaging Laboratory, Department of Electrical and Computer Engineering, Boston University, 8 Saint Mary’s Street, Boston, Massachusetts 02215 Department of Physics, Boston University, 8 Saint Mary’s Street, Boston, Massachusetts 02215 Starlab NV, Excelsiorlaan 40-42, B-1930 Zaventem, Belgium ~Received 7 May 1999!