Counterfactual quantum-information transfer

TL;DR

This paper presents a counterfactual quantum information transfer scheme enabling the transfer of quantum data without physical particles traveling between distant parties, using entanglement without interaction.

Contribution

It introduces a novel counterfactual scheme for quantum information transfer and entanglement generation that does not require prior entanglement or classical communication.

Findings

Successful demonstration with photon and electron-spin qubits

Scheme enables entanglement without interaction

No need for prior entanglement sharing or classical communication

Abstract

We demonstrate quantum information can be transferred between two distant participants without any physical particles travelling between them. The key procedure of the counterfactual scheme is to entangle two nonlocal qubits with each other without interaction, so the scheme can also be used to generate nonlocal entanglement counterfactually. We here illustrate the scheme by using flying photon qubits and stationary electron-spin qubits assisted by quantum dots inside double-sided optical microcavities. Unlike the typical teleportation, the present scheme does not require prior entanglement sharing or classical communication between the two distant participants.