We consider a three-port single-level quantum dot system with one input and two output leads. Instead of considering an empty dot, we study the situations that two input electrons co-tunnel through the quantum dot occupied by one or two dot electrons. We show that electron entanglement can be generated via the co-tunneling processes when the dot is occupied by two electrons, yielding non-local spin-singlet states at the output leads. When the dot is occupied by a single electron, net spin-singlet final states could be generated by injecting polarized electrons to the dot system. When the input electrons are unpolarized, we show that by carefully arranging model parameters non-local spin-triplet electrons can also be obtained at the output leads if the dot-electron spin remains unchanged in the final state.
A comment on: Universal control of superexchange in linear triple quantum dots with an empty mediator
在最近的预印本arXiv：2203.15521 G. X. Chan，P. Huang，and X. Wang声称在（1，0，1）电荷配置中的三重量子点超交换表现出作为中间点失谐的函数的符号变化（从正到负）。此外，他们的主张是，对于特定的点间失谐值，存在电荷最佳点。他们的分析是基于哈伯德模型和他们所称的完全解释-相互作用方法。所有这些发现都已经由M. J. Rančić和G. Burkard在参考文献Phys. Rev. B 96，201304（R）（2017）中基于哈伯德模型。参考文献arXiv：2203.15521中未提及该手稿。我已经要求作者紧急修改预印本，并将他们的工作定位于之前进行的研究-他们目前拒绝这样做，引用该页。在接受前修改预印本不是他们的风格。这与一些人物非常相似的风格一起使我得出结论，他们故意误导科学界，并试图采用其他人的工作和想法作为自己的。
Charge and spin qubits in interacting quantum dots coupled to Rashba-active leads
Università di Napoli Federico II（那不勒斯费德里科二世大学）；INFN, Sezione di Napoli（意大利国家核物理研究所那不勒斯分部）；Physics Department “E.R. Caianiello”, Università degli Studi di Salerno（萨莱诺大学E.R.凯亚涅洛物理系）；INFN - Sezione collegata di Salerno（意大利国家核物理研究所萨莱诺协作分部）；SPIN-CNR and Dip. di Fisica E. Pancini - Università di Napoli Federico II（CNR自旋研究中心与那不勒斯费德里科二世大学E.潘奇尼物理系）
Tuning arrays with rays: Physics-informed tuning of quantum dot charge states
National Institute of Standards and Technology（美国国家标准与技术研究院）；Intel Corporation（英特尔公司）；Joint Center for Quantum Information and Computer Science（量子信息与计算机科学联合中心）；University of Maryland（马里兰大学）
