Distributed Quantum Computation via Entanglement Forging and Teleportation

TL;DR

This paper presents methods to perform distributed quantum computation without quantum correlations by classically forging entangled states, expanding the capabilities of quantum processor integration.

Contribution

It introduces a novel approach to implement nonlocal quantum circuits without quantum correlations, using classically forged Bell states and teleportation equivalence.

Findings

Nonlocal quantum circuits can be implemented without quantum correlations.

Classically forged Bell states enable teleportation equivalent to quantum state tomography.

The method increases measurement overhead and requires auxiliary qubits.

Abstract

Distributed quantum computation is a practical method for large-scale quantum computation on quantum processors with limited size. It can be realized by direct quantum channels in flying qubits. Moreover, the pre-established quantum entanglements can also play the role of quantum channels with local operations and classical channels. However, without quantum correlations like quantum channels and entanglements, the entanglement forging technique allows us to classically forge the entangled states with local operations and classical channels only. In this paper, we demonstrate the methods to implement a nonlocal quantum circuit on two quantum processors without any quantum correlations, which is based on the fact that teleportation with classically forged Bell states is equivalent to quantum state tomography. In compensation, the overhead of single-shot measurement will increase, and several auxiliary qubits are required. Our results extend the possibility of integrating quantum processors. We expect that our methods will complement the toolbox of distributed quantum computation, and facilitate the extension of the scale of quantum computations.