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arXiv · 2103.07907

Geometric Manipulation of a Decoherence-Free Subspace in Atomic Ensembles

Dongni Chen·Si Luo·Ying-Dan Wang·Stefano Chesi·Mahn-Soo Choi
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Abstract

We consider an ensemble of atoms with $\Lambda$-type level structure trapped in a single-mode cavity, and propose a geometric scheme of coherent manipulation of quantum states on the subspace of zero-energy states within the quantum Zeno subspace of the system. We find that the particular subspace inherits the decoherence-free nature of the quantum Zeno subspace and features a symmetry-protected degeneracy, fulfilling all the conditions for a universal scheme of arbitrary unitary operations on it.

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Dongni Chen, Si Luo, Ying-Dan Wang, Stefano Chesi, Mahn-Soo Choi. 2021-03-14. Geometric Manipulation of a Decoherence-Free Subspace in Atomic Ensembles. https://doi.org/10.1103/physreva.105.022627

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