Linear-optical programmable quantum router

TL;DR

This paper proposes a linear-optical scheme for a programmable quantum router that coherently routes photon qubits based on control qubits without altering the signal's polarization, with potential for signal-dependent routing.

Contribution

It introduces a novel linear-optical implementation of a programmable quantum router that preserves the signal's polarization state during routing.

Findings

Polarization-encoded photon qubits are coherently routed to multiple spatial modes.

The scheme maintains the polarization state of the signal photon during routing.

Potential for generalization to signal-dependent routing is discussed.

Abstract

This paper presents a scheme for linear-optical implementation of a programmable quantum router. Polarization encoded photon qubit is coherently routed to various spatial modes according to the state of several control qubits. In our implementation, the polarization state of the signal photon does not change under the routing operation. We also discuss generalization of the scheme that would allow to obtain signal dependent routing.