We theoretically investigate the coherent time of a single qubit in a RbCl quantum well (QW) with asymmetric Gaussian confinement potential (AGCP) using the Pekar-type variational method. Additionally, we utilize Fermi’s golden rule to consider strong coupling between electrons and longitudinal optical phonons in the QW with an electric field applied. The results show that the coherence time changes with AGCP QW’s height, height of the QW, polaron radius and electric field. Moreover, we also show that the coherence time is minimized to \( \tau = 412.0\;{\text{ps}} \) in a confinement potential range \( R = 0.19\;{\text{nm}} \). Thus we conclude that these tunable parameters of the QW are vital for adjusting the coherence time and deciding the stability of the qubit.

中文翻译：

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具有不对称高斯约束势和外加电场的RbCl量子阱中的量子位相干效应

我们理论上使用Pekar型变分方法研究了具有非对称高斯约束势（AGCP）的RbCl量子阱（QW）中单个量子位的相干时间。此外，我们利用费米的黄金定律来考虑施加电场的情况下量子阱中电子与纵向光学声子之间的强耦合。结果表明，相干时间随AGCP QW的高度，QW的高度，极化子半径和电场而变化。此外，我们还表明，在限制电位范围\（R = 0.19 \; {\ text {nm}} \）中，相干时间被最小化为\（\ tau = 412.0 \; {\ text {ps }} \）。因此，我们得出的结论是，QW的这些可调参数对于调整相干时间和决定量子位的稳定性至关重要。