English

Low-depth measurement-based deterministic quantum state preparation

Quantum Physics 2025-10-10 v1

Abstract

We present a low-depth amplitude encoding method for arbitrary quantum state preparation. Building on the foundation of an existing divide-and-conquer algorithm, we propose a method to disentangle the ancillary qubits from the final state. Our method is measurement-based but deterministic, and offers an alternative approach to existing state preparation algorithms. It has circuit depth O(n), which is known to be optimal, and O(2^n) ancilla qubits, which is close to optimal. We illustrate our method through detailed worked examples of both a ``dense'' state and a W-state. We discuss extensions to the algorithm resetting qubits mid-circuit, and construct hybrid algorithms with varying space and circuit depth complexities.

Keywords

Cite

@article{arxiv.2510.08267,
  title  = {Low-depth measurement-based deterministic quantum state preparation},
  author = {Roselyn Nmaju and Fiona Speirits and Sarah Croke},
  journal= {arXiv preprint arXiv:2510.08267},
  year   = {2025}
}
R2 v1 2026-07-01T06:26:54.885Z