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arXiv · 2209.09212

Control of Localized Multiple Excitation Dark States in Waveguide QED

Raphael Holzinger·Ricardo Gutierrez-Jauregui·Teresa Hönigl-Decrinis·Gerhard Kirchmair·Ana Asenjo-Garcia·Helmut Ritsch
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Abstract

Subradiant excited states in finite chains of two-level quantum emitters coupled to a one-dimensional reservoir are a resource for superior photon storage and controlled photon manipulation. Typically, states storing multiple excitations exhibit fermionic correlations and are thus characterized by an anti-symmetric wavefunction, which makes them hard to prepare experimentally. Here we identify a class of quasi-localized dark states with up to half of the qubits excited, which appear for lattice constants that are an integer multiple of the guided-mode wavelength. They allow for a high-fidelity preparation and minimally invasive read out in state-of-the-art setups. In particular, we suggest an experimental implementation using a coplanar wave-guide coupled to superconducting transmon qubits on a chip. As free space and intrinsic losses are minimal, virtually perfect dark states can be achieved even for a low number of qubits, enabling fast preparation and manipulation with high fidelity.

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Raphael Holzinger, Ricardo Gutierrez-Jauregui, Teresa Hönigl-Decrinis, Gerhard Kirchmair, Ana Asenjo-Garcia, Helmut Ritsch. 2022-10-18. Control of Localized Multiple Excitation Dark States in Waveguide QED. https://doi.org/10.1103/physrevlett.129.253601

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