Deterministic quantum state transfer from an electronic charge qubit to a photonic polarization qubit

TL;DR

This paper demonstrates a deterministic method for transferring an unknown quantum state from an electronic charge qubit to a photonic polarization qubit, with fidelity affected by charge decoherence.

Contribution

It introduces a deterministic quantum state transfer protocol between charge and photonic qubits without postselection, advancing quantum communication techniques.

Findings

State transfer is deterministic and does not require postselection.

Fidelity decreases non-monotonically with charge decoherence.

The protocol enables reliable quantum information transfer between electronic and photonic systems.

Abstract

Building on an earlier proposal for the production of polarization-entangled microwaves by means of intraband transitions in a pair of quantum dots, we show how this device can be used to transfer an unknown single-qubit state from electronic charge to photonic polarization degrees of freedom. No postselection is required, meaning that the quantum state transfer happens deterministically. Decoherence of the charge qubit causes a non-monotonic decay of the fidelity of the transferred state with increasing decoherence rate.