Prepare-and-Send Universal Blind Quantum Computation: Difference between revisions

The following Universal Blind Quantum Computation (UBQC) protocol uses the unique feature of Measurement Based Quantum Computation '''[[Supplementary Information#Measurement Based Quantum Computation|(MBQC)]]''' that separates the classical and quantum parts of a computation. MBQC requires a set of initial entangled states, called graph states for computation. Here, we shall use a special family of graph states, '''[[Supplementary Information#Brickwork States|brickwork states]]''' which are universal (can implement any quantum operation) for X-Y measurements and do not leak any specific data about the computation during preparation. The protocol can be divided into three stages: preparation, computation and output correction.<br/>

Preparation stage includes a partially quantum Client preparing and sending quantum states to the Server who constructs the required brickwork state. Computation stage involves interaction. Output Correction involves retrieval of correct output from the results sent by the Server. We shall discuss below three protocols with different attributes but same functionality. All UBQC protocols discussed below require Client to prepare the required quantum states for computation and send those to the Server, hence the name ''Prepare and Send UBQC''. Protocol 1a deals with a partially quantum Client capable of preparing initial quantum states for the construction of brickwork state with classical input/output computation. Protocols 1b and 1c are extensions to accommodate quantum inputs and quantum outputs, respectively.

  '''Protocol 1a:''' ''Client is assumed to be able to prepare quantum states.''