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arXiv · 1504.07454

EPR pairing dynamics in Hubbard model with resonant $U$

X. Z. Zhang·Z. Song
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Abstract

We study the dynamics of the collision between two fermions in Hubbard model with on-site interaction strength $U$. The exact solution shows that the scattering matrix for two-wavepacket collision is separable into two independent parts, operating on spatial and spin degrees of freedom, respectively. The S-matrix for spin configuration is equivalent to that of Heisenberg-type pulsed interaction with the strength depending on $U$ and relative group velocity $\upsilon _{r}$. This can be applied to create distant EPR pair, through a collision process for two fermions with opposite spins in the case of $\left\vert \upsilon _{r}/U\right\vert =1$,\ without the need for temporal control and measurement process. Multiple collision process for many particles is also discussed.

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X. Z. Zhang, Z. Song. 2015-04-28. EPR pairing dynamics in Hubbard model with resonant $U$. https://doi.org/10.1038/srep18323

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