Projects per year
Abstract
Blind quantum computing (BQC) allows a client to have a server carry out a quantum computation for them such that the client's input, output, and computation remain private. A desirable property for any BQC protocol is verification, whereby the client can verify with high probability whether the server has followed the instructions of the protocol or if there has been some deviation resulting in a corrupted output state. A verifiable BQC protocol can be viewed as an interactive proof system leading to consequences for complexity theory. We previously proposed [A. Broadbent, J. Fitzsimons, and E. Kashefi, in Proceedings of the 50th Annual Symposium on Foundations of Computer Science, Atlanta, 2009 (IEEE, Piscataway, 2009), p. 517] a universal and unconditionally secure BQC scheme where the client only needs to be able to prepare single qubits in separable states randomly chosen from a finite set and send them to the server, who has the balance of the required quantum computational resources. In this paper we extend that protocol with additional functionality allowing blind computational basis measurements, which we use to construct another verifiable BQC protocol based on a different class of resource states. We rigorously prove that the probability of failing to detect an incorrect output is exponentially small in a security parameter, while resource overhead remains polynomial in this parameter. This resource state allows entangling gates to be performed between arbitrary pairs of logical qubits with only constant overhead. This is a significant improvement on the original scheme, which required that all computations to be performed must first be put into a nearestneighbor form, incurring linear overhead in the number of qubits. Such an improvement has important consequences for efficiency and faulttolerance thresholds.
Original language  English 

Article number  012303 
Number of pages  27 
Journal  Physical Review A 
Volume  96 
Issue number  1 
DOIs  
Publication status  Published  5 Jul 2017 
Fingerprint Dive into the research topics of 'Unconditionally verifiable blind quantum computation'. Together they form a unique fingerprint.
Projects
 1 Finished

Measurement based quantum computing and it's relation to other quantum models
1/03/08 → 31/07/13
Project: Research
Profiles

Elham Kashefi
 School of Informatics  Personal Chair in Quantum Computing
 Laboratory for Foundations of Computer Science
 Foundations of Computation
Person: Academic: Research Active