Resilience of hybrid optical angular momentum qubits to turbulence

TL;DR

This paper demonstrates that hybrid optical angular momentum qubits can be used for alignment-free quantum communication through turbulent channels with high fidelity, utilizing q-plates for encoding and decoding.

Contribution

It shows the experimental feasibility of turbulence-resilient hybrid qubits for quantum communication using an innovative error-filtering decoding method.

Findings

Achieved unit fidelity in turbulent conditions

Implemented alignment-free quantum communication

Demonstrated error filtering via degrees of freedom

Abstract

Recent schemes to encode quantum information into the total angular momentum of light, defining rotation-invariant hybrid qubits composed of the polarization and orbital angular momentum degrees of freedom, present interesting applications for quantum information technology. However, there remains the question as to how detrimental effects such as random spatial perturbations affect these encodings. Here, we demon- strate that alignment-free quantum communication through a turbulent channel based on hybrid qubits can be achieved with unit transmission fidelity. In our experiment, alignment-free qubits are produced with q-plates and sent through a homemade tur- bulence chamber. The decoding procedure, also realized with q-plates, relies on both degrees of freedom and renders an intrinsic error-filtering mechanism that maps errors into losses.