论文标题
离子导体AGCRSE $ _2 $中的光学声子和磁弹性耦合
Optical phonons and magneto-elastic coupling in the ionic conductor AgCrSe$_2$
论文作者
论文摘要
Agcrse $ _2 $是一个超级离子导体的一个例子，最近引起了其低导热率的关注。在这里，我们使用反射率实验研究了在14 K和374 K之间的有序阶段中AgCRSE $ _2 $的光学性质。远红外光学响应以三个声子模式为主导，而在可见范围内观察到六个频带跃迁。从我们的分析中，我们发现声子参数在Néel温度周围显示出有趣的温度依赖性，指向小磁弹性耦合。此外，模式的寿命表明，三频过程占主导地位，并且光学声子腐烂成超级离世过渡涉及的低能声学模式。最后，我们通过分析反射率数据中的Fabry-Perot干扰条纹检测到一个少量的自由电荷载体响应。
AgCrSe$_2$ is an example of a super-ionic conductor that has recently attracted attention for its low thermal conductivity. Here we investigate the optical properties of AgCrSe$_2$ in the ordered phase between 14 K and 374 K using reflectivity experiments. The far infrared optical response is dominated by three phonon modes, while six interband transitions are observed in the visible range. From our analysis we find that the phonon parameters display an interesting temperature dependence around the Néel temperature, pointing to a small magneto-elastic coupling. In addition, the lifetimes of the modes indicate that three-phonon processes dominate and the optical phonons decay into low energy acoustic modes involved in the super-ionic transition. Finally, we detect a small free charge carrier response through the analysis of Fabry-Perot interference fringes in our reflectivity data.
