  A crucial open problem in large-scale quantum networks is how to efficiently
transmit quantum data among many pairs of users via a common data-transmission
medium. We propose a solution by developing a quantum code division multiple
access (q-CDMA) approach in which quantum information is chaotically encoded to
spread its spectral content, and then decoded via chaos synchronization to
separate different sender-receiver pairs. In comparison to other existing
approaches, such as frequency division multiple access (FDMA), the proposed
q-CDMA can greatly increase the information rates per channel used, especially
for very noisy quantum channels.
