Quantum no-key protocols for secret transmission of quantum and   classical message
  A theoretical framework of quantum no-key (QNK) protocol has been presented. As its applications, we develop three kinds of QNK protocols: the practical QNK protocols, the QNK protocol based on quantum perfect encryption, and the QNK protocols based on Boolean function computing. The security of these protocols is based on the laws of quantum mechanics, other than computational hypothesis. 
Li Yang, Min Liang, Bao Li, Lei Hu, and Ling-An Wu
quant-ph