Multi-cavity strong coupling to an electron spin ensemble: spectral and dark-state signatures

2026/08/06 by P. Oehrl, B. Pérez González, A. Dunaev +5
Physics and Astronomy · #quant-ph #cond-mat.mtrl-sci

paper · pdf

17 pages, 9 figures

arxiv created 2026/08/06 · arxiv updated 2026/08/07

Abstract

Spin ensembles are considered as potential candidates for quantum memory and quantum enhanced sensing applications. Here, we explore the controlled coupling of multiple superconducting microwave cavities to a spin ensemble, which shows signatures of strong coupling and, due to the multi-mode character, the formation of dark states. In particular, the latter are of interest, as they provide a potential pathway to enhance memory times and enable protected storage of non-classical states in spin ensembles due to the suppressed coupling to the circuit environment. We model the spin multi-cavity hybrid to reproduce the spectra and extract characteristic coupling strengths using the input-output formalism.

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