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arXiv · 1106.0507

Electron spin ensemble strongly coupled to a three-dimensional microwave cavity

Eisuke Abe·Hua Wu·Arzhang Ardavan·John J. L. Morton
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Abstract

We demonstrate the strong coupling between an electron spin ensemble and a three-dimensional cavity in a reflection geometry. We also find that an anticrossing in the cavity/spin spectrum can be observed under conditions that the collective coupling strength $g_c$ is smaller than the spin linewidth $γ_s$ or the cavity linewidth. We identify a ratio of $g_c$ to $γ_s$ ($g_c/γ_s >$ 0.64) as a condition to observe a splitting in the cavity frequency. Finally, we confirm that $g_c$ scales with $\sqrt{N}$, where $N$ is the number of polarized spins.

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Eisuke Abe, Hua Wu, Arzhang Ardavan, John J. L. Morton. 2011-06-02. Electron spin ensemble strongly coupled to a three-dimensional microwave cavity. https://doi.org/10.1063/1.3601930

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