Device Independent Quantum Private Query

TL;DR

This paper introduces the first device-independent quantum private query protocol, ensuring security without trusting the quantum devices, by leveraging local CHSH game techniques.

Contribution

It presents a novel device-independent QPQ protocol that removes the need for trusting the entangled states in existing schemes.

Findings

First device-independent QPQ protocol proposed

Utilizes local CHSH game for device independence

Connects with Yang et al.'s scheme for implementation

Abstract

In Quantum Private Query (QPQ), a client obtains values corresponding to his query only and nothing else from the server and the server does not get any information about the queries. Giovannetti et al. (Phys. Rev. Lett., 2008) gave the first QPQ protocol and since then quite a few variants and extensions have been proposed. However, none of the existing protocols are device independent, i.e., all of them assume implicitly that the entangled states supplied to the client and the server are as prescribed. In this work, we exploit the idea of local CHSH game and connect it with the scheme of Yang et al. (Quantum Inf. Process., 2014) to present the concept of device independent QPQ protocol for the first time.