News of the WeekCommunications

Quantum Encryption Takes First Step to Orbit

See allHide authors and affiliations

Science  23 Oct 1998:
Vol. 282, Issue 5389, pp. 605-606
DOI: 10.1126/science.282.5389.605

You are currently viewing the summary.

View Full Text

Log in to view the full text

Log in through your institution

Log in through your institution


For sending a secret code, nothing beats quantum mechanics--at least in the laboratory. To be useful, however, quantum messages, such as the numerical "keys" required to decode secure messages sent by other means, will have to travel long distances, for example, from the ground to a military or telecommunications satellite. Now a team of physicists has transmitted a key over a distance of 1 kilometer in the chill night air of the New Mexico desert using a broad laser beam that is yet so faint that each bit of data is represented by the polarization of a single photon.