Quantum broadcasting multiple blind signature protocol based on three-particle partial entanglement

Abstract

<sec>Recently, a quantum broadcasting multiple blind signature scheme based on GHZ state has been proposed, which could be used to settle the problem that a message is so important that it needs to be signed by multiple signatories, in order to guarantee the message privacy: none of signatories can acquire the content of the message they have signed. Maybe it can be applied to an E-bank system. For example, a large amount of money has to be transferred through E-bank system on the internet. The E-bank system operator submits the request to the bank after filling the application form including payment amount, bank transfer account and some other information. When the request arrives, the bank clerk signs to approve. However, it is not enough, it has to ask the manager for authority, and then it needs to be signed by the manager. In the whole process, all the signatories cannot learn what they have signed, but the application form has been recorded in the E-bank system. So, once disagreement takes place, the bank can track the message sender. </sec><sec>In this paper, we present a new quantum broadcasting multiple blind signature scheme which is based on a three-particle partial entanglement state. Comparing with the original scheme, the partial entanglement state is utilized in our new scheme in place of the GHZ state, and this does not bring down the security of the scheme. Particularly, using the partial entanglement state can not only save the entanglement resource to some extent, but also make the scheme much easier to be realized. As is well known, It is not easy to keep the maximum entanglement state shared among the participants in the whole quantum communication process. By using the partial entanglement in place of the maximum entanglement can improve the new scheme applicability to make it more practical. It is also indicated that multi-qubit entangled systems which are partially entangled can be efficiently used as a resource in quantum information processing with perfect performance.</sec>