Interpreting S-Parameter Spectra in Coupled Resonant Systems: The Role of Probing Configurations

2024/05/13 by Wang, Jiongjie, Xiao, Jiang
#FOS: Physical sciences #Mesoscale and Nanoscale Physics (cond-mat.mes-hall)

paper · doi:10.48550/arxiv.2405.07555

Abstract

The S-parameter S₂₁ is widely used to characterize the resonant properties of various systems. However, we demonstrates that the reliability of S₂₁ as a true indicator of system resonances depends heavily on the specific probing setup employed. While point-probe or weak probes preserve the integrity of the S₂₁ spectrum and accurately reflect system resonances, multi-point and strong probes can introduce significant discrepancies. These discrepancies can manifest as misleading features such as repulsive level anti-crossing or attractive level crossing, even in systems that are fundamentally uncoupled. This highlights the critical importance of selecting appropriate probing techniques to ensure a precise evaluation of system resonances.

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