Helium-free cryostat for resonance fluorescence measurements

用于共振荧光测量的无氦低温恒温器

• 批准号: 444418722
• 金额: --
• 依托单位: Arbeitsgruppe Experimentelle Physik
• 依托单位国家: 德国
• 项目类别: Major Research Instrumentation
• 财政年份: 2020
• 资助国家: 德国
• 起止时间: 2019-12-31 至 无数据
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/444418722?language=en
• 关键词: Helium; free; cryostat; resonance; fluorescence

The subject of this application is an optical setup for measuring spatially resolved resonance fluorescence at low temperatures (4K – 300K). The instrument is intended to be used in particular for the spectroscopy of low-dimensional solids, such as quantum dots. Quantum dots are nanometer-sized semiconductor structures, which spatially confine charge carriers (electrons/holes), such that quantum phenomena become observable. Among those are (besides energy and charge quantization) exchange interaction and magnetic phenomena, which make quantum dots atom-like model systems. There are fundamental differences, though. For example, quantum dots can be contacted and electrically tuned. Also, external magnetic and electric potentials can compete with the confinement potentials and thus allow for wide quantum tunability. With these properties, quantum dots are not only of fundamental scientific interest. They also form a bridge to present-day , nanometer-size commercial semiconductor structures and offer perspectives as electronic and optical building blocks in future (quantum) information technologies. In this regard, the combination of electronic and optical spectroscopy is of particular interest. The applicant’s group can refer to sizable and relevant previous experience. Here, spatially resolved resonance fluorescence spectroscopy has proven to be a particularly fruitful method. Because of its high spatial and energy resolution, it makes it possible to observe the dynamics of single electrons in a single quantum dot. Examples for such dynamical processes that can be followed optically and with time resolution are: Electron tunneling, Auger recombination, internal photoeffect, and internal electron capture. Furthermore, non-equilibrium states can be prepared and their relaxation into equilibrium can be observed. The proposed instrument will be employed for these and related experiments on quantum dots and other low-dimensional structures. In particular, the setup will significantly strengthen the scientific work in project A01 of the Collaborative Research Centre 1242 “Non-Equilibrium Dynamics of Condensed Matter in the Time Domain". Further scientific work that will benefit from this instrument include DFG project “Auger effects in quantum dots” and a proposal within the Priority Programme 2244 „2D-Materials”.

本申请的主题是用于在低温（4K -300 K）下测量空间分辨共振荧光的光学装置。该仪器旨在特别用于低维固体（例如量子点）的光谱学。量子点是纳米尺寸的半导体结构，其在空间上限制电荷载流子（电子/空穴），使得量子现象变得可观察。其中包括（除了能量和电荷量子化）交换相互作用和磁现象，这使得量子点成为类似原子的模型系统。不过，两者之间存在着根本性的差异。例如，量子点可以被接触和电调谐。此外，外部磁势和电势可以与限制势竞争，从而实现宽量子可调性。有了这些特性，量子点不仅具有基本的科学意义。它们还形成了通往当今纳米尺寸商业半导体结构的桥梁，并提供了未来（量子）信息技术中电子和光学构建模块的前景。在这方面，电子和光学光谱的组合是特别感兴趣的。申请人的团体可以参考相当大的和相关的以前的经验。在这里，空间分辨共振荧光光谱已被证明是一个特别富有成效的方法。由于它的高空间和能量分辨率，它使观察单个量子点中单个电子的动力学成为可能。可以用光学和时间分辨率跟踪的这种动力学过程的例子有：电子隧穿、俄歇复合、内部光电效应和内部电子捕获。此外，可以制备非平衡态，并且可以观察到它们弛豫到平衡态。拟议的仪器将用于量子点和其他低维结构的这些实验和相关实验。特别是，该机构将大大加强1242合作研究中心A01项目“时域凝聚态物质的非平衡动力学”的科学工作。将受益于该仪器的进一步科学工作包括DFG项目“量子点中的俄歇效应”和优先计划2244“2D材料”中的一项提案。