Wong Joe, Krisch Michael, Farber Daniel L, Occelli Florent, Schwartz Adam J, Chiang Tai-C, Wall Mark, Boro Carl, Xu Ruqing
Lawrence Livermore National Laboratory, University of California, Post Office Box 808, Livermore, CA 94551, USA.
Science. 2003 Aug 22;301(5636):1078-80. doi: 10.1126/science.1087179.
We report an experimental determination of the phonon dispersion curves in a face-centered cubic (fcc) delta-plutonium-0.6 weight % gallium alloy. Several unusual features, including a large elastic anisotropy, a small-shear elastic modulus C', a Kohn-like anomaly in the T1[011] branch, and a pronounced softening of the [111] transverse modes, are found. These features can be related to the phase transitions of plutonium and to strong coupling between the lattice structure and the 5f valence instabilities. Our results also provide a critical test for theoretical treatments of highly correlated 5f electron systems as exemplified by recent dynamical mean field theory calculations for delta-plutonium.
我们报告了对面心立方（fcc）δ-钚-0.6重量%镓合金中声子色散曲线的实验测定。发现了几个不寻常的特征，包括大的弹性各向异性、小的剪切弹性模量C'、T1[011]分支中的类科恩反常以及[111]横向模式的明显软化。这些特征可能与钚的相变以及晶格结构和5f价态不稳定性之间的强耦合有关。我们的结果还为高度相关的5f电子系统的理论处理提供了关键检验，最近对δ-钚的动态平均场理论计算就是一个例子。
