English

Remotely Preparing Many Qubits with a Single Photon

Quantum Physics 2026-04-23 v2

Abstract

A single photon in a superposition of dd modes naturally encode a dd-dimensional quantum system, a so-called qudit. We show that such superpositions can be leveraged to achieve a quantum speed-up of remote remote state preparation (RSP): a primitive for several quantum network protocols. For a superposition over d2d\geq 2 modes, the photon state can encode up to Log2(d){\rm Log}_2(d) qubits, which we exploit in a proposed reflection based RSP protocol with multiple variations. For single qubit RSP, we achieve a performance comparable to the best known existing schemes but with reduced requirements for phase stabilization. For many qubit RSP the achievable success rates remain high despite needing exponentially many temporal modes, since only one photon needs to be transmitted and detected to prepare multiple qubits. By simultaneously preparing many qubits at once, we bypass limited qubit lifetimes limited qubit lifetimes and improve fidelities beyond what is achievable with existing RSP protocols.

Keywords

Cite

@article{arxiv.2604.03495,
  title  = {Remotely Preparing Many Qubits with a Single Photon},
  author = {Tzula B. Propp and Benedikt Tissot and Anders S. Sørensen and Stephanie D. C. Wehner},
  journal= {arXiv preprint arXiv:2604.03495},
  year   = {2026}
}
R2 v1 2026-07-01T11:53:33.061Z