High-fidelity quantum gates for OAM qudits on quantum memory

TL;DR

This paper presents a method for implementing high-fidelity single-qudit gates using light modes with orbital angular momentum in quantum memory, enhancing high-dimensional quantum information processing.

Contribution

It introduces a logical qudit encoding method ensuring quasi-cyclicity and demonstrates high-fidelity gates based on orbital angular momentum in Raman quantum memory.

Findings

High fidelity of single-qudit transformations achieved

Optimal conditions identified for different system dimensions

Protocol based on orbital angular momentum conversion in quantum memory

Abstract

The application of high-dimensional quantum systems (qudits) in quantum computing and communications seems to be a promising avenue due to the possibility of increasing the amount of information encoded in one physical carrier. In this work, we propose a method for implementing single-qudit gates for qudits based on light modes with orbital angular momentum. Method for logical qudits encoding, which ensures the quasi-cyclicity of operations, is introduced. Based on the protocol for converting the orbital angular momentum of light in the Raman quantum memory scheme [Vashukevich E.A. et. al. PRA, 101, 033830 (2020)], we show that the considered gates provide an extremely high level of fidelity of single-qudit transformations. We also compare quantum gates' properties for systems of different dimensions and find the optimal conditions for carrying out transformations in the protocol under consideration.