Realization of reliable solid-state quantum memory for photonic polarization-qubit

TL;DR

This paper demonstrates a high-fidelity solid-state quantum memory for photonic polarization qubits using rare-earth ion doped crystals, achieving near-perfect storage and retrieval of quantum states, advancing quantum network technology.

Contribution

The authors realize a reversible, high-fidelity quantum memory for photonic polarization states in a compact solid-state device using an atomic frequency comb in rare-earth crystals.

Findings

Achieved 0.998 process fidelity in storage and retrieval.

Demonstrated reliable quantum memory at the single-photon level.

Enabled potential for scalable quantum networks.

Abstract

Faithfully storing an unknown quantum light state is essential to advanced quantum communication and distributed quantum computation applications. The required quantum memory must have high fidelity to improve the performance of a quantum network. Here we report the reversible transfer of photonic polarization states into collective atomic excitation in a compact solid-state device. The quantum memory is based on an atomic frequency comb (AFC) in rare-earth ion doped crystals. We obtain up to 0.998 process fidelity for the storage and retrieval process of single-photon-level coherent pulse. This reliable quantum memory is a crucial step toward quantum networks based on solid-state devices.