Open fiber-based cavity for spectroscopix experiments in semiconductor quantum optics

我们申请了一个稳定的开放光纤腔的调查半导体结构方面的量子光学问题。该腔将用于在低于5 K的低温下以长期稳定的方式达到广泛的材料系统的强轻物质耦合制度，同时赋予纳米范围或更好的空间分辨率。开放腔将被应用于广泛的量子光学研究的范围广泛的材料系统，包括里德伯激子，钙钛矿，胶体纳米片和TMDC。详细地说，我们将研究（a）强耦合区中大块晶体和微晶中里德伯激子的标度性质。(b)基于TMDCs和钙钛矿的极化激元凝聚体的量子态。测量的光子统计的发射和量子态层析成像技术是感兴趣的。(c)半导体量子技术的耦合特性。例如，量子点是否可以用作从半导体结构发射的量子光的短期量子缓冲器的问题。开放腔内光-物质相互作用强度的精确可调谐性对于匹配量子缓冲器的各个组件的带宽将是非常有益的。(d)钝化氧化镧层中超灵敏跃迁的空间分辨特性，这对于量子传感应用是非常有希望的。(e)空间分辨光谱的稀土硫化物薄膜，以发展这类材料的磁光性能的透彻理解。腔谐振的可调谐性、模体积和所研究的样品位置使得有可能追求量子光学问题的全新方法，特别是在半导体系统中，由于在创建高质量布拉格谐振器结构方面的巨大技术挑战，迄今为止难以达到强耦合制度。对于这些材料以及仅在有限的实验条件下才能达到强光-物质耦合的材料，可以预期可以实现纳秒级的持久相干特性，这对应于量子光学半导体光谱学的巨大进步。

We apply for a stabilized open fiber cavity for investigations of semiconductor structures with respect to questions of quantum optics. The cavity will be used to reach the strong ligh-matter coupling regime in a long-term stable manner for a wide range of material systems at cryogenic temperatures below 5 K, while simultaneously granting spatial resolution in the nanometer range or better. The open cavity will be applied to a wide range of quantum optical investigations for a wide range of material systems, including Rydberg excitons, Perovskites, colloidal nanoplatelets and TMDCs. In detail, we will study (a) the scaling properties of Rydberg excitons in bulk crystals and microcrystals in the strong coupling regime. (b) the quantum states of polariton condensates based on TMDCs and perovskites. Measurements of photon statistics of the emission and quantum state tomography techniques are of interest here. (c) coupling properties of semiconductor quantum technologies. For example, the question whether quantum dots may be utilized as short-term quantum buffers for quantum light emitted from semiconductor structures. The precise tunability of the light-matter interaction strength within the open cavity will be highly beneficial for matching the bandwidth of the individual components of the quantum buffer. (d) the spatially resolved properties of hypersensitive transitions in passivated Lanthanum Oxide Layers, which are highly promising for quantum sensing applications. (e) spatially resolved spectroscopy on rare-earth sulfide thin films in order to develop a thorough understanding of the magneto-optical properties of this class of materials. The tunability of the cavity resonance, the mode volume and the investigated sample position make it possible to pursue fundamentally new approaches to quantum-optical questions especially in semiconductor systems for which is has been hard so far to reach the strong coupling regime due to huge technological challenges in creating high quality Bragg resonator structures. For these materials and also for materials where strong light-matter coupling could only be reached for limiting experimental conditions, it is to be expected that long-lasting coherence properties on the scale of nanoseconds may be realized, which corresponds to huge progress in terms of quantum-optical semiconductor spectroscopy.