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arXiv · 2207.00775

Ultrafast adiabatic passages in ultrastrongly coupled light-matter systems

Xun Gao·Liwei Duan·Pinghua Tang·Junlong Tian·Zhongzhou Ren·Enrique Solano·Jie Peng
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Abstract

We have obtained the solutions of the multimode quantum Rabi model when all modes have identical frequencies $\omega$, including dark states $|\phi_K\rangle$ with at least $K$ $(K=1,2,3,\ldots)$ photons. Extended to the multiqubit case, they lie close to another dark state $\vert \psi\rangle$ with at most one photon in the spectrum. Taking advantages of such solutions, we find a linear and symmetry-protected adiabatic passage through $\vert \psi\rangle$ to fast generate arbitrary single-photon $M$-mode $W$ states $\vert W_M\rangle$ with exactly the same speed. The effective minimum energy gap during the adiabatic evolution is further enlarged to $0.63\omega$ when Stark shifts are included, such that arbitrary $\vert W_M\rangle$ can be ultrafast generated in $1.55\times 2\pi\omega^{-1}$ with fidelity $99\%$, indepedent of $M$. This work reveals the existence of linear ultrafast adiabatic passages in light-matter systems.

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Xun Gao, Liwei Duan, Pinghua Tang, Junlong Tian, Zhongzhou Ren, Enrique Solano, Jie Peng. 2022-07-02. Ultrafast adiabatic passages in ultrastrongly coupled light-matter systems. https://arxiv.org/abs/2207.00775

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