Preparation of non-classical photon states in laser-driven quantum-dot-cavity systems under the influence of acoustic phonons

声声子影响下激光驱动量子点腔系统中非经典光子态的制备

• 批准号: 419036043
• 负责人: Professor Dr. Vollrath Martin Axt
• 金额: --
• 依托单位: Lehrstuhl für Theoretische Physik III (Quantentheorie der kondensierten Materie)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2019
• 资助国家: 德国
• 起止时间: 2018-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/419036043?language=en
• 关键词: Preparation; non; classical; photon; states

In this project we shall explore theoretically possibilities to prepare non-classical photon states, such as, e.g., Schrödinger-cat states, Fock states or polarization entangled two-pair states, in quantum-dot-cavity systems. Such states can not only be used to test the basics of quantum mechanics but also serve as central building blocks for possible applications in photonics, quantum-information-processing and quantum-cryptography.We shall investigate in how far the photon state in a quantum-dot-cavity system can be manipulated by different laser excitations. Of particular interest are the new physical effects evoked by the interaction with lattice oscillations (phonons) which cannot be avoided in semiconductor based quantum dot systems. Phonons may be an obstacle for the preparation; but it is also possible that phonon-assisted processes may enable new preparation protocols.We shall also study how far the generation of photon-pairs, which arise from the decay of a biexciton (i.e. a state with two electron-hole pairs) in the resonator, can be influenced by external laser fields and what role phonons play in this case. Also the so far unexplored possibility to switch between different types of entanglement will be investigated.Two-time correlation functions shall be evaluated avoiding the usually invoked quantum regression theorem which is not valid for systems with a non-Markovian environment (here provided by the phonons). Two-time correlation functions are directly connected to measurable quantities and contain important information about the non-classical properties of photons. New physical insights in particular into the significance of non-Markovian effects are expected to be found by simulating key quantities of photonic systems such as the indistinguishability, the coherence, the degree of entanglement as well as by recording the photon statistics of N-photon bundles.All calculations within this project will be performed using numerically complete path-integral methods without any approximation to the usually used models. For the quantum-dissipative multi-level systems studied here, such a complete treatment has become available only recently due to a methodological progress reached by the group of the applicant. First studies reveal that even advanced well established approximate methods lead to large deviations from the numerically complete results in praxis-relevant parameter ranges. The errors are particularly large for photonic properties, which are the focus oft the present project. Thus, the numerically complete treatment is decisive for reaching conclusive results.

在这个项目中，我们将探讨在量子点腔体系中，在诸如Schrödinger-Cat状态，Fock状态或极化纠缠的两对态的诸如Schrödinger-Cat状态，Fock状态或极化状态的理论可能性。这样的状态不仅可以用于测试量子力学的基础知识，而且还可以用作光子学，量子信息处理和量子 - 晶体术中可能应用的中心构建块。我们应在量子点腔体系统中的光子状态在多远中进行研究。特别令人感兴趣的是与晶格振荡（声子）相互作用所引起的新物理效应，这些效果无法在基于半导体的量子点系统中避免。声子可能是准备准备的障碍。但是，我们还可能会研究声子辅助的过程。我们还应研究光子对的产生的距离，这是由biexciton（即具有两个电子孔对的状态）在谐振器中引起的，它可以受到外部激光场以及在这种情况下的角色扮演的影响。同样，将研究到迄今为止在不同类型的纠缠之间切换的可能性。应评估两个时间相关函数，以避免使用通常被调用的量子回归定理，该定理对于具有非马克维亚环境的系统无效（此处由声子提供）。两次相关函数直接连接到可测量的数量，并包含有关照片的非古典性质的重要信息。预计将通过模拟光子系统的关键数量（例如无法区分性，一致性，纠缠程度以及通过记录N-PHOTON捆绑包的光子统计量）来发现非马克维亚效应的重要性的新新物理见解。该项目中的所有计算都将使用数值完整的近似图表来进行。对于这里研究的量子性多层系统，由于申请人组达到的方法学进展，这种完整的治疗才能获得。第一项研究表明，即使是高级建立的近似方法，也导致了与实践相关的参数范围的数值完整结果。对于光子特性而言，这些误差特别大，这是本项目的重点。这是在数值完整的治疗中决定得出结论性结果的决定性。