Caporaletti F, Chumakov A I, Rüffer R, Monaco G
Dipartimento di Fisica, Università di Trento, I-38123 Povo, Trento, Italy.
ESRF-The European Synchrotron, CS40220, 38043 Grenoble Cedex 9, France.
Rev Sci Instrum. 2017 Oct;88(10):105114. doi: 10.1063/1.5008868.
Time-domain interferometry (TDI) based on nuclear resonant scattering of synchrotron radiation by Mössbauer nuclei is a promising technique to study slow dynamics at the interatomic length scale. In order to improve the efficiency of this technique, a new TDI scheme is developed involving the use of a nuclear absorber with a two-line energy spectrum combined with a single-line spectrum. Different from other TDI setups, the issue of external vibrations is much reduced since the two absorbers are at rest and no velocity transducer is used. This allows measuring beating patterns with satisfying statistical accuracy and contrast up to 350 ns. We report here the characterization of the experimental setup necessary for the implementation of this new scheme. The model required for the description of the beating pattern produced by a three-line spectrum system is also discussed in detail. Finally, we report some results for the dynamics of the prototypical glass-former ortho-terphenyl to demonstrate the possibilities offered by this new scheme.
基于穆斯堡尔原子核同步辐射核共振散射的时域干涉测量（TDI）是一种研究原子间长度尺度慢动力学的有前途的技术。为了提高该技术的效率，开发了一种新的TDI方案，该方案涉及使用具有双线能谱并结合单线能谱的核吸收体。与其他TDI装置不同，由于两个吸收体处于静止状态且未使用速度传感器，外部振动问题大大减少。这使得能够以令人满意的统计精度测量拍频模式，对比度可达350纳秒。我们在此报告实施此新方案所需的实验装置的特性。还详细讨论了描述三线谱系统产生的拍频模式所需的模型。最后，我们报告了典型玻璃形成体邻三联苯动力学的一些结果，以证明此新方案提供的可能性。
