Bidirectional multi-photon communication between remote superconducting nodes

TL;DR

This paper demonstrates a superconducting circuit testbed capable of bidirectional multi-photon state transfer and entanglement between remote nodes using shaped wavepackets, advancing quantum communication capabilities.

Contribution

It introduces a novel superconducting setup with remote nodes that can transfer and entangle multi-photon states bidirectionally using time-domain shaped wavepackets.

Findings

Successful transfer of individual and superposition Fock states

Bidirectional state transfer can be performed simultaneously

Remote entanglement of superconducting nodes achieved

Abstract

Quantum communication testbeds provide a useful resource for experimentally investigating a variety of communication protocols. Here we demonstrate a superconducting circuit testbed with bidirectional multi-photon state transfer capability using time-domain shaped wavepackets. The system we use to achieve this comprises two remote nodes, each including a tunable superconducting transmon qubit and a tunable microwave-frequency resonator, linked by a 2 m-long superconducting coplanar waveguide, which serves as a transmission line. We transfer both individual and superposition Fock states between the two remote nodes, and additionally show that this bidirectional state transfer can be done simultaneously, as well as used to entangle elements in the two nodes.