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arXiv · 2310.10153

Photoinduced $\eta$-pairing correlation in the Hubbard ladder

Ryota Ueda·Kazuhiko Kuroki·Tatsuya Kaneko
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Abstract

We investigate the staggered correlation of the on-site pairs, the so-called $\eta$-pairing correlation, induced by pump electric fields in the Hubbard model on the ladder lattice. Employing the time-evolution method based on exact diagonalization, we compute the photoinduced $\eta$-pairing correlation with different strengths of the interchain hopping. When the pump field is polarized along the chain direction, the $\eta$-pairing correlation is noticeably induced in the weakly coupled double-chain region, where the pairing property is similar to the $\eta$ pairing in the single-chain Hubbard model. On the other hand, the pump field polarized along the rung direction prominently induces the $\eta$-pairing correlation in the strong interchain coupling regime, where the pair correlations developing across rungs strongly contribute to the $\eta$ pairing. Based on the local rung approximation, which is valid in the strong interchain coupling regime, we discuss the origin of the photoinduced pair.

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Ryota Ueda, Kazuhiko Kuroki, Tatsuya Kaneko. 2023-10-16. Photoinduced $\eta$-pairing correlation in the Hubbard ladder. https://doi.org/10.1103/physrevb.109.075122

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