Blind Oracular Quantum Computation

TL;DR

This paper introduces Blind Oracular Quantum Computation (BOQC), a scheme where an oracle is a separate node in a quantum network, enabling secure, low-quantum-power client interactions with a quantum server.

Contribution

It formalizes BOQC as a secure, network-based quantum computation model with minimal qubit requirements, extending client-server quantum computing with oracle separation.

Findings

BOQC is proven to be blind, ensuring server cannot learn client computations.

BOQCo achieves minimal physical qubits while maintaining security.

The scheme is applicable to solid-state quantum networks.

Abstract

In the standard oracle model, an oracle efficiently evaluates an unknown classical function independent of the quantum algorithm itself. Quantum algorithms have a complex interrelationship to their oracles; for example the possibility of quantum speedup is affected by the manner by which oracles are implemented. Therefore, it is physically meaningful to separate oracles from their quantum algorithms, and we introduce one such separation here. We define the Blind Oracular Quantum Computation (BOQC) scheme, in which the oracle is a distinct node in a quantum network. Our work augments the client-server setting of quantum computing, in which a powerful quantum computer server is available on the network for discreet use by clients on the network with low quantum power. In BOQC, an oracle is another client that cooperates with the main client so that an oracular quantum algorithm is run on the server. The cooperation between the main client and the oracle takes place (almost) without communication. We prove BOQC to be blind: the server cannot learn anything about the clients' computation. This proof is performed within the composable security definitions provided by the formalism of Abstract Cryptography. We enhance the BOQC scheme to be runnable with minimal physical qubits when run on a solid-state quantum network; we prove that this scheme, which we refer to as BOQCo (BOQC-optimized), possesses the same security as BOQC.