Mollow triplet emission and high-harmonic generation involving isolated impurity atoms of semiconductors in a strong terahertz field

强太赫兹场中涉及半导体孤立杂质原子的莫洛三重态发射和高次谐波产生

• 批准号: 390200638
• 负责人: Dr. Fanqi Meng
• 金额: --
• 依托单位: Physikalisches Institut
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2017
• 资助国家: 德国
• 起止时间: 2016-12-31 至 2019-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/390200638?language=en
• 关键词: Mollow; triplet; emission; harmonic; generation

This proposal asks for funding for a short research visit at the University of California at Santa Barbara (UCSB) in order to perform atomic-physics-type experiments on isolated dopant atoms in semiconductors with the university's free-electron laser (FEL). The proposal's two topics are the Mollow triplets-the frequency analogue of Rabi oscillations in a strong quasi-continuous terahertz field, and the generation of higher harmonics by charge carriers which, after ionization, are accelerated in the oscillating field and recollide with the dopant ions. These topics are strongly motivated by analog phenomena of atomic physics with gasses, where notably the observation of higher harmonics by the recollision phenomenon represents the foundation for the hot research field of attosecond physics. The embedding of isolated atoms in a host crystal has the consequence that nonlinear optical effects (with rather long coherence times) occur at much lower field strength and photon energy than in free atoms. Such phenomena could hardly be studied in the past for a lack of suitable radiation sources and measurement techniques. Building on our prior studies, we intend to take advantage of the UCSB-FEL's unique properties for the observation of the effects addressed above. These properties are the very small bandwidth of the FEL's long THz pulses which are favorable for the addressing of individual quantum states and the observation of newly generated sidebands, and the low radiation frequencies accessible (down to a few hundred GHz) which support the generation of high orders of the harmonics upon carrier-ion recollision.

该提案要求在加利福尼亚大学圣塔芭芭拉分校（UCSB）进行简短的研究访问，以便在半导体中对孤立的掺杂原子进行原子化原子型实验，并使用该大学的自由电子激光（FEL）进行。该提案的两个主题是Mollow Triplets - 强烈的准连续Terahertz场中Rabi振荡的频率类似物，以及电荷载体在电离后通过电离载体产生较高的谐波，这些载体在振荡场中所代表，并带有掺杂剂离子。这些主题是由与气体的原子物理学的模拟现象强烈的动机，在这种情况下，回忆现象对较高的谐波观察到了较高的谐波，这代表了Attosecond Physics的热研究领域的基础。分离的原子在宿主晶体中的嵌入的结果是，非线性光学效应（相当长的相干时间）在磁场强度和光子能量低于自由原子下发生。由于缺乏合适的辐射源和测量技术，这种现象几乎无法研究。在我们先前的研究的基础上，我们打算利用UCSB-FEL的独特特性来观察上述效果。这些特性是FEL的长THZ脉冲的很小带宽，这些脉冲有利于解决单个量子状态和新产生的新产生的边带的观察，以及可访问的低辐射频率（下降到几百GHz），这些频率支持携带者对携带者的高阶生成。