高压下ZnSe纳米带的结构相变及拉曼散射研究  

Structural Transition and Raman Scattering of ZnSe Nanoribbons under High Pressure

作　　者：金恩姬[1] 姚立德[2] 王菲菲[2] 沈希[2] 游淑洁[2] 杨留响[2] 蒋升[2] 李延春[3] 朱恪[2] 刘玉龙[2] 邹炳锁[2] 刘景[3] 靳常青[2] 禹日成[2] 

机构地区：[1]北京石油化工学院数理系,北京102617 [2]中国科学院物理研究所,北京100190 [3]中国科学院高能物理研究所同步辐射实验室,北京100039

出　　处：《高压物理学报》2009年第4期241-246,共6页Chinese Journal of High Pressure Physics

基　　金：国家自然科学基金(10774168;50621061);国家重点基础研究发展计划(2005CB623602)

摘　　要：利用高压原位角散X射线衍射实验研究了ZnSe纳米带的结构稳定性。发现样品在12.6 GPa附近存在一个从立方闪锌矿型到立方岩盐矿型的结构相变,并且在相变点附近存在较大的体积收缩,相对体积变化率达13%。利用Birch-Murnaghan状态方程拟合,得到了闪锌矿相的体弹模量约为56 GPa,略低于体材料的体弹模量(约67 GPa);并得到其立方岩盐矿相的体弹模量约为116 GPa。高压拉曼散射实验结果表明,横光学声子模散射峰在5.5 GPa压力附近发生劈裂,纵光学声子模散射峰在12.8 GPa压力以上逐渐消失。根据角散实验的体弹模量数据,计算得到了闪锌矿相中对应不同声子模式的格林爱森常数。Structural stability of ZnSe nanoribbons was analyzed by means of high-pressure in situ angular dispersive X-ray diffraction（ADXD）.The pressure-induced structural transition from the Zinc blende（ZB） to a rocksalt（RS） phase occurs at about 12.6 GPa,and at the transition point the relative volume reduction is close to 13%.By fitting the relative volume-pressure relation to the Birch-Murnaghan equation of states,the bulk modulus B0 for the ZB and RS phases were determined.The values of B0 are 56 GPa（B′0=4） and 116 GPa（B′0=4） for the former and the latter,respectively.According to the measured high-pressure Raman scattering spectra,the TO phonon modes split into two peaks at about 5.5 GPa,and the LO peak gradually disappears above 12.8 GPa due to the semiconductor-metal transition.Using the value of the bulk modulus obtained from the ADXD experiments,the corresponding mode Grüneisen parameters are obtained for the ZB phase.

关 键 词：ZnSe纳米带 高压原位角散X射线衍射 结构相变 高压拉曼散射 

分 类 号：O521.2[理学—高压高温物理]