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Spin amplification in realistic systems

Ivan Iakoupov1,2,*, Victor M. Bastidas2, Yuichiro Matsuzaki2,3, Shiro Saito2, and William J. Munro1,2

  • *Contact author: ivan.iakoupov@oist.jp
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Phys. Rev. Research 8, 033227 – Published 26 August, 2026

DOI: https://doi.org/10.1103/4nqk-9t5s

Abstract

Spin amplification is the process that ideally increases the number of excited spins when one of them is excited initially. We show that by applying optimal control techniques to design classical drive pulse shapes, spin amplification can be achieved in a previously unexplored fast regime, with amplification times comparable to the intrinsic interaction timescale. This is an order of magnitude faster than the previous protocols and makes spin amplification possible even with significant decoherence and inhomogeneity in the spin system. The initial spin excitation can be delocalized over the entire ensemble, which is a more typical situation when a photon is collectively absorbed by the spins. We focus on the superconducting persistent-current artificial atoms and the Rydberg atoms as spins.

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Phys. Rev. Research 8, 033227– Published 26 August, 2026
  • Received 18 September 2024
  • Accepted 14 July 2026
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