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arXiv · 2505.09322

Light-Matter Interaction in dispersive Superconducting Circuit QED

Harsh Arora·Jay Deshmukh·Ansh Das·R. Vijay·Baladitya Suri
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Abstract

It is well known that superconducting waveguides strongly attenuate the propagation of electromagnetic waves with frequencies beyond the superconducting gap. In circuit QED, the interaction between non-linear charge qubits and superconducting resonators invariably involves the qubit coupling to a large set of resonator modes. So far, strong dispersion effects near and beyond the superconducting-gap have been ignored in quantization models. Rather, it is assumed that the superconducting resonator behaves ideally across the large frequency intervals. We present a quantization approach which includes the superconducting frequency-dependent surface impedance and demonstrate that superconducting dispersion plays a role in determining the effective light-matter interaction cut-off.

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Harsh Arora, Jay Deshmukh, Ansh Das, R. Vijay, Baladitya Suri. 2025-05-14. Light-Matter Interaction in dispersive Superconducting Circuit QED. https://arxiv.org/abs/2505.09322

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