The Research Of Blind Quantum Computation Over Noise Channels

Based on the characteristic of qubit superposition,quantum computation can realize the parallel computing,which makes its computing speed much more faster than a classical one.The concept of blind quantum computation is proposed to enable an ordinary user with classical ability to accomplish her quantum computation task,which is a new kind of secure delegated quantum computation model.Blind quantum computation is a combination of quantum information processing and quantum cryptography,where an ordinary client who has limited or no quantum ability can outsource her quantum computation tasks to a quantum server to obtain her desired outputs,at the same time,keep her inputs,outputs and algorithms private.In reality,in addition to considering the ability of ordinary users,the problem of noise in a quantum channel is unavoidable.Therefore,the research of blind quantum computation needs to consider the practical truth.The focus of this thesis is to make the blind quantum computation more realistic and apply to an appropriate scenario.The following is the main contents:1.Multi-server blind quantum computation over collective-noise channels.This protocol introduces two different types of logical Bell states as quantum computation resources,which can resist collective-dephasing noise and collective-rotation noise,respectively.At the same time,this protocol presents four fault-tolerant versions against the collective-noise of the existing multi-server blind quantum computation protocols,including two double-server blind quantum computation schemes and two triple-server blind quantum computation schemes.In the proposed double-server blind quantum computation schemes,a completely classical client can safely delegate her quantum computation tasks to two quantum servers that cannot communicate with each other.In the proposed triple-server blind quantum computation schemes,an almost classical client(only has the ability to access the quantum channel)can accomplish her quantum computation tasks by means of three quantum servers that can communicate with each other.Furthermore,the four proposed schemes can meet both correctness and blindness.2.Authenticated semiquantum dialogue with secure delegated quantum computation over a collective noise channel.Semiquantum communication permits a communication party with only limited quantum ability(i.e.“classical” ability)cansecurely communicate with a powerful quantum counterpart.In a quantum dialogue scenario,two communicants mutually transmit their respective secret messages and may have equal power(such as two classical parties).Based on the delegated quantum computation model,this protocol extends the original semiquantum model to the authenticated semiquantum dialogue protocols,where two “classical” participants can mutually transmit secret messages without any information leakage and quantum operations are securely delegated to a server with quantum capabilities.To make the proposed protocols more realistic,the quantum channel is a collective noise channel and the quantum server is untrusted.The security analysis shows that the proposed protocols are robust even when the delegated quantum server is a powerful adversary.