Collective effects in the emission from semiconductor microcavities

半导体微腔发射的集体效应

• 批准号: 167777060
• 负责人: Professor Dr. Marc Alexander Aßmann
• 金额: --
• 依托单位: Lehrstuhl für Experimentelle Physik II
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2010
• 资助国家: 德国
• 起止时间: 2009-12-31 至 2017-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/167777060?language=en
• 关键词: Collective; effects; emission; semiconductor; microcavities

The present proposal aims at investigations of collective effects in the optical emission from semiconductor microcavities. Besides applying modern spectroscopic techniques to semiconductor systems, special emphasis will also be placed on the development of novel spectroscopic tools. Photon correlation spectroscopy using a streak camera - as developed in Dortmund - is the most adequate method here. The technique enables us to perform measurements of statistical dependences of photon emission processes with a temporal resolution of two picoseconds. As a complementary technique, a setup for correlation measurements using homodyne detection shall be used. This technique offers improved temporal resolution of about 100 femtoseconds and phase sensitivity, but also requires sophisticated data analysis. The systems to be investigated are quantum dot microcavity lasers and colloidal nanostructures, so called nanoplatelets. Concerning quantum dot lasers, we will investigate the question how coherence builds up during a pulse. At the beginning of a pulse, many quantum dots are still in the excited state, so a collective interaction with the light field inside the cavity seems probable. This should result in a significant short-lived increase of photon number fluctuations during the initial phase of pulse formation. In combination with systematic variation of the detuning between the cavity mode and the quantum dot ensemble, the results will allow for a much deeper understanding of the dynamics of quantum dot lasers. Colloidal nanoplatelets are well known for their anisotropy and the presence of a transition towards giant oscillator strength even without the presence of a cavity. The microscopic origin of this transition is not known yet, but collective effects seem like a reasonable explanation. Time-resolved investigations of the coherence of the emission should clarify, whether stimulated emission, superradiance or other effects are taking place. Another experimental technique that shall be realized is quantum optical excitation spectroscopy. The main idea behind this technique lies in the fact that the response of any non-linear system does not only depend on the mean intensity of that excitation, but also on its quantum optical properties in terms of fluctuations around the mean value. Using systematic variations of intensity fluctuations of the optical excitation, we will realize this technique and test some predictions. For example, the response from a non-linear system is expected to show a significant increase in the noise of the response when excited with a light field of strongly fluctuating intensity. This increase should already take place way below the non-linear threshold. Therefore it should open up an interesting and convenient possibility to identify and characterize non-linearities.

本文旨在研究半导体微腔光发射中的集体效应。除了将现代光谱技术应用于半导体系统外，还将特别强调新型光谱工具的开发。在多特蒙德开发的利用条纹相机的光子相关光谱学是这里最合适的方法。该技术使我们能够以2皮秒的时间分辨率对光子发射过程的统计依赖性进行测量。作为一种补充技术，我们建立了一套使用纯差检测应使用的相关测量装置。这项技术提供了大约100飞秒的时间分辨率和相位灵敏度，但也需要复杂的数据分析。要研究的系统是量子点微腔激光器和胶体纳米结构，即所谓的纳米血小板。关于量子点激光器，我们将研究在脉冲期间相干性如何建立的问题。在脉冲开始时，许多量子点仍处于激发态，因此与腔内光场的集体相互作用似乎是可能的。这将导致在脉冲形成的初始阶段光子数波动的显著短期增加。结合腔模式和量子点系综之间失谐的系统变化，结果将允许对量子点激光器的动力学有更深入的理解。胶体纳米血小板以其各向异性和向巨振强度的过渡而闻名，即使没有空腔的存在。这种转变的微观起源尚不清楚，但集体效应似乎是一个合理的解释。对发射相干性的时间分辨研究应能澄清是否发生了受激发射、超辐射或其他效应。另一个需要实现的实验技术是量子光激发光谱。这种技术背后的主要思想在于，任何非线性系统的响应不仅取决于该激发的平均强度，还取决于其量子光学性质，即在平均值周围的波动。利用光激发强度波动的系统变化，我们将实现这一技术并测试一些预测。例如，当受到强波动光场的激励时，非线性系统的响应预计会显示出响应噪声的显著增加。这种增长应该已经远远低于非线性阈值。因此，它应该为识别和表征非线性提供了一种有趣而方便的可能性。

项目成果

Quantum-Optically Enhanced STORM (QUEST) for Multi-Emitter Localization

用于多发射器定位的量子光学增强型 STORM (QUEST)

• DOI: 10.1038/s41598-018-26271-1
• 发表时间: 2018
• 期刊: Scientific Reports
• 影响因子: 4.6
• 作者: Marc Aßmann

Streak camera imaging of single photons at telecom wavelength

电信波长单光子条纹相机成像

• DOI: 10.1063/1.5004110
• 发表时间: 2018
• 期刊: Applied Physics Letters
• 影响因子: 4
• 作者: Markus Allgaier;Vahid Ansari;Christof Eigner;Viktor Quiring;Raimund Ricken;John Matthew Donohue;Thomas Czerniuk;Marc Aßmann;Manfred Bayer;Benjamin Brecht;Christine Silberhorn
• 通讯作者: Christine Silberhorn