1] Department of Physics and Astronomy and Institute for Quantum Science and Engineering, Texas A&M University, College Station, Texas 77843-4242, USA [2] Kazan Federal University, Kazan 420008, Russia [3] Kazan Physical-Technical Institute of the Russian Academy of Sciences, Kazan 420029, Russia.
1] Department of Physics and Astronomy and Institute for Quantum Science and Engineering, Texas A&M University, College Station, Texas 77843-4242, USA [2] Institute of Applied Physics of the Russian Academy of Sciences, Nizhny Novgorod 603950, Russia [3] N.I. Lobachevsky State University, Nizhny Novgorod 603950, Russia.
Nature. 2014 Apr 3;508(7494):80-3. doi: 10.1038/nature13018. Epub 2014 Mar 16.
The concepts and ideas of coherent, nonlinear and quantum optics have been extended to photon energies in the range of 10-100 kiloelectronvolts, corresponding to soft γ-ray radiation (the term used when the radiation is produced in nuclear transitions) or, equivalently, hard X-ray radiation (the term used when the radiation is produced by electron motion). The recent experimental achievements in this energy range include the demonstration of parametric down-conversion in the Langevin regime, electromagnetically induced transparency in a cavity, the collective Lamb shift, vacuum-assisted generation of atomic coherences and single-photon revival in nuclear absorbing multilayer structures. Also, realization of single-photon coherent storage and stimulated Raman adiabatic passage were recently proposed in this regime. More related work is discussed in a recent review. However, the number of tools for the coherent manipulation of interactions between γ-ray photons and nuclear ensembles remains limited. Here we suggest and implement an efficient method to control the waveforms of γ-ray photons coherently. In particular, we demonstrate the conversion of individual recoilless γ-ray photons into a coherent, ultrashort pulse train and into a double pulse. Our method is based on the resonant interaction of γ-ray photons with an ensemble of nuclei with a resonant transition frequency that is periodically modulated in time. The frequency modulation, which is achieved by a uniform vibration of the resonant absorber, owing to the Doppler effect, renders resonant absorption and dispersion both time dependent, allowing us to shape the waveforms of the incident γ-ray photons. We expect that this technique will lead to advances in the emerging fields of coherent and quantum γ-ray photon optics, providing a basis for the realization of γ-ray-photon/nuclear-ensemble interfaces and quantum interference effects at nuclear γ-ray transitions.
相干、非线性和量子光学的概念和思想已经扩展到光子能量范围为 10-100 千电子伏特，对应于软γ射线辐射（当辐射在核跃迁中产生时使用的术语），或者等效地，硬 X 射线辐射（当辐射由电子运动产生时使用的术语）。在这个能量范围内，最近的实验成果包括朗之万区的参量下转换的演示、腔中的电磁感应透明、集体拉曼位移、真空辅助原子相干的产生以及在核吸收多层结构中的单光子复活。此外，在这个区域中最近还提出了单光子相干存储和受激拉曼绝热通过的实现。更多相关的工作在最近的一篇综述中进行了讨论。然而，用于相干地操控γ射线光子与核系综之间相互作用的工具数量仍然有限。在这里，我们提出并实现了一种高效的方法来实现γ射线光子的相干波型控制。具体而言，我们演示了将单个无反冲γ射线光子转换为相干的超短脉冲串和双脉冲的方法。我们的方法基于γ射线光子与具有共振跃迁频率的核系综的共振相互作用，该共振跃迁频率在时间上周期性地调制。频率调制是通过共振吸收体的均匀振动（由于多普勒效应）来实现的，这使得共振吸收和色散都与时间有关，从而使入射γ射线光子的波型得以成形。我们期望这项技术将推动相干和量子γ射线光子光学领域的发展，为实现γ射线光子/核系综界面和核γ射线跃迁中的量子干涉效应提供基础。
