Hamiltonian Benchmark of a Solid-State Spin-Photon Interface for Computation

TL;DR

This paper provides an exact Hamiltonian analysis of a solid-state spin-photon interface, revealing fundamental limits and robustness of quantum protocols like photon generation, gates, and cluster states.

Contribution

It introduces a full Hamiltonian solution for spin-photon interfaces, capturing multi-mode effects and entanglement, advancing precise quantum protocol modeling.

Findings

Photon-photon gates are highly sensitive to imperfections.

Linear photonic clusters are only mildly affected by imperfections.

Photon-number superpositions are nearly unaffected by realistic imperfections.

Abstract

Light-matter interfaces are pivotal for quantum computation and communication. While typically analyzed using single-mode or open-quantum-system approximations, these models often neglect multi-mode field states and light-matter entanglement, hindering exact protocol modeling. Here, we solve the full Hamiltonian dynamics of a solid-state spin-photon interface for three key protocols: the generation of photon-number superpositions, a controlled photon-photon gate, and the production of photonic cluster states. By deriving exact fidelities, we identify fundamental performance limits. Our results reveal that while realistic imperfections severely limit photon-photon gates, they only slightly affect linear photonic clusters and are nearly harmless for photon-number state superpositions.