Search for vibronic excitations in CeAuAl3 - continuation (p11633)

<b>Abstract:</b>Recently, time-of-flight neutron spectroscopy in polycrystalline samples of CeCuAl3 has provided putative evidence for a so-called vibronic mode – a combined crystal field - phonon excitation. These types of modes may be responsible for certain forms of magnetically mediated superconductivity or non-Fermi liquid behavior. Our measurement on single-crystal CeAuAl3 performed on the PUMA (p10684, see references) revealed a weakly dispersive excitation at energy 7.9 meV, which is clearly magnetically driven and connected to phonons. However to better understand the nature of this hybridized excitation, more phonon measurements are necessary. Therefore we propose to determine the detailed dispersion of the low lying optical phonons in the energy range between 12-50 meV.<b>Place:</b>Heinz Meier-Leibnitz Zentrum, Garching, Germany (MLZ)<br><b>Instruments:</b><br>PUMA (https://mlz-garching.de/puma)<b>Date: </b><br>Tue, 29. Nov 2016 to Sun, 04. Dec 2016<b>Disclaimer:</b>Abstract is not modified version of the abstract from original scientific proposal submitted to MLZ. Data are published exactly as they were send to us after the end of experiments (automatic email by NICOS). Authenticity of the data can be verified by the data scientists at MLZ, feel free to contact them.<br>

<b>摘要：</b>近期，针对CeCuAl3多晶样品开展的飞行时间中子谱（time-of-flight neutron spectroscopy）实验，为所谓的振动模（vibronic mode）——即晶体场与声子的复合激发——提供了推测性证据。此类振动模或与若干磁介导超导（magnetically mediated superconductivity）行为或非费米液体（non-Fermi liquid）现象存在关联。我们依托PUMA谱仪（实验编号p10684，详见参考文献）对CeAuAl3单晶体开展的测量实验，观测到能量为7.9 meV的弱色散激发信号，该信号明确由磁相互作用主导且与声子存在关联。然而，为更深入阐明该杂化激发的本质，需开展更多声子相关测量。因此，本提案拟测定能量区间12~50 meV内低能光学声子的精细色散关系。<b>实验地点：</b>德国加尔兴海因茨·迈尔-莱布尼茨中子源（Heinz Meier-Leibnitz Zentrum, MLZ）<br><b>实验仪器：</b><br>PUMA谱仪（https://mlz-garching.de/puma）<b>实验日期：</b><br>2016年11月29日（周二）至2016年12月4日（周日）<b>免责声明：</b>本摘要未对提交至MLZ的原始科学提案摘要进行修改。实验结束后，我们直接原样发布由NICOS自动邮件发送至我方的实验数据。数据真实性可由MLZ的数据科学家核验，欢迎联系咨询。