Resource-efficient linear-optical quantum router

TL;DR

This paper presents a resource-efficient, all-linear-optical quantum router capable of directing photonic qubits based on control qubits, with optimized success probability and scalability for multiple signals.

Contribution

It introduces a novel linear-optical quantum routing scheme that meets key requirements and can be generalized for improved success rates and multi-qubit routing.

Findings

Successfully demonstrates a linear-optical quantum routing principle.

Optimizes success probability using a tunable controlled-phase gate.

Extends the scheme to route multiple signal qubits with a single control.

Abstract

All-linear-optical scheme for fully featured quantum router is presented. This device directs the signal photonic qubit according to the state of one control photonic qubit. In the introduction we formulate the list of requirements imposed on a fully quantum router. Then we describe our proposal showing the exact principle of operation on a linear-optical scheme. Subsequently we provide generalization of the scheme in order to optimize the success probability by means of a tunable controlled-phase gate. At the end, we show how one can modify the device to route multiple signal qubits using the same control qubit.