论文标题
由于三电子杂化双孔量子的电子相关性引起的分子形成和光谱
Molecular formations and spectra due to electron correlations in three-electron hybrid double-well qubits
论文作者
论文摘要
我们表明，系统的完整配置相互作用（FCI）计算可以预测多体波的固有空间和自旋结构，这是基于GAAS不对称双重量子点的三电子混合量子的函数的函数。具体而言，与弱相互作用的情况相比，将整个三电子双点混合量子乘以作为积分单元的情况，这表明预测的光谱模式源自较强的电子相关性，体现了Wigner Molecules（WMS）的形成。 WM形成的特征包括：（1）强烈抑制相对于非相互作用 - 电子建模的能量差距，以及（2）（2）在与左和右井中与两极分子占领相关的状态之间产生的一对避免的交叉口的出现。 Wigner分子是一个与每个孔中电子定位相关的物理实体，无法通过先前使用的独立粒子或二个位点 - 超标式理论建模来捕获杂种量子。通过共同使用FCI适应的诊断工具（例如电荷和自旋密度）以及有条件的概率分布，深入研究了强大的WMS的出现。此外，计算能量光谱是库仑排斥力强度（在恒定失调时）的函数，以补充对有助于WM出现的因素的彻底分析。我们报告了与最近的实验测量相似的一致性。当前的多孔量子点的FCI方法可以直接扩展以治疗Valleytronic两波段Si/Sige Hybrid Qubits，最近确认了WMS的核心作用。
We show that systematic full configuration-interaction (FCI) calculations enable prediction of the energy spectra and the intrinsic spatial and spin structures of the many-body wave functions as a function of the detuning parameter for the case of three-electron hybrid qubits based on GaAs asymmetric double quantum dots. Specifically, in comparison with the case of weak interactions and treating the entire three-electron double-dot hybrid qubit as an integral unit, it is shown that the predicted spectroscopic patterns, originating from strong electron correlations, manifest the formation of Wigner molecules (WMs). Signatures of WM formation include: (1) a strong suppression of the energy gaps relative to the non-interacting-electrons modeling, and (2) the appearance of a pair of avoided crossings arising between states associated with two-electron occupancies in the left and right wells. The Wigner molecule is a physical entity associated with electron localization within each well and it cannot be captured by the previously employed independent-particle or two-site-Hubbard theoretical modeling of the hybrid qubits. The emergence of strong WMs is investigated in depth through the concerted use of FCI-adapted diagnostic tools like charge and spin densities, as well as conditional probability distributions. Furthermore, the energy spectrum as a function of the strength of the Coulomb repulsion (at constant detuning) is calculated in order to complement the thorough analysis of the factors contributing to WM emergence. We report remarkable agreement with recent experimental measurements. The present FCI methodology for multi-well quantum dots can be straightforwardly extended to treat valleytronic two-band Si/SiGe hybrid qubits, where the central role of the WMs was confirmed recently.
