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arXiv · 1412.5635

Two-axis spin squeezing of two-component BEC via a continuous driving

Wen Huang·Yan-Lei Zhang·Chang-Ling Zou·Xu-Bo Zou·Guang-Can Guo
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Abstract

In two-component BEC, the one-axis twisting Hamiltonian leads to spin squeezing with the limitation that scales with the number of atoms as $N^{-\frac{2}{3}}$. We propose a scheme to transform the one-axis twisting Hamiltonian into a two-axis twisting Hamiltonian, resulting in enhanced spin squeezing $\propto N^{-1}$ approaching the Heisenberg limit. Instead of pulse sequences, only one continuous driving field is required to realizing such transforming, thus the scheme is promising for experiment realizations, to an one-axis twisting Hamiltonian. Quantum information processing and quantum metrology may benefit from this method in the future.

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Wen Huang, Yan-Lei Zhang, Chang-Ling Zou, Xu-Bo Zou, Guang-Can Guo. 2014-12-17. Two-axis spin squeezing of two-component BEC via a continuous driving. https://doi.org/10.1103/physreva.91.043642

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