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Eliminating interactions between non-neighboring qubits in the preparation of cluster states in quantum molecules

Guo-Ping Guo·Xiao-Jie Hao·Tao Tu·Zhi-Cheng Zhu·Guang-Can Guo
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Abstract

We propose a scheme to eliminate the effect of non-nearest-neighbor qubits in preparing cluster state with double-dot molecules. As the interaction Hamiltonians between qubits are Ising-model and mutually commute, we can get positive and negative effective interactions between qubits to cancel the effect of non-nearest-neighbor qubits by properly changing the electron charge states of each quantum dot molecule. The total time for the present multi-step cluster state preparation scheme is only doubled for one-dimensional qubit chain and tripled for two-dimensional qubit array comparing with the time of previous protocol leaving out the non-nearest-neighbor interactions.

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Guo-Ping Guo, Xiao-Jie Hao, Tao Tu, Zhi-Cheng Zhu, Guang-Can Guo. 2008-04-24. Eliminating interactions between non-neighboring qubits in the preparation of cluster states in quantum molecules. https://doi.org/10.1140/epjb/e2008-00053-9

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