hcp金属的高压拉曼散射光谱研究

High-Pressure Raman Spectroscopy of hcp Metals

通过高压拉曼光谱可以从微观角度研究高压下材料的晶格动力学行为。然而,受金刚石荧光与金属样品强反射的影响,高压下金属样品的拉曼光谱信号较难获得。为此,发展了一种简易的金刚石对顶砧倾角散射高压拉曼光谱技术,可实现六角密排结构(hcp)金属样品的高压拉曼光谱信号测量。以hcp金属Be为例,通过测量最高压力达73 GPa时的剪切拉曼模E_(2g),获得了其弹性常数C_(44)随压力的变化关系。所提出的金刚石对顶砧倾角散射高压拉曼光谱技术为研究金属材料的成键状态、电子结构、声子-电子耦合效应提供一种新手段。

The lattice dynamics behavior of materials under high pressure can be studied by high-pressure Raman spectroscopy.However,Raman spectroscopic signal of metal samples at high pressure is difficult to obtain due to the fluorescence of the diamond in diamond anvil cell(DAC)and the strong reflection of the samples.In this work,we use DAC inclination scattering method to mitigate background noise.As a consequence,Raman spectroscopic signal of the hcp metal samples(Be,Re,Os)under high pressure have been achieved.In the case of Be,the pressure dependence of elastic constant C_(44) is obtained by measuring the shear Raman mode E_(2g) at pressure up to 73 GPa.The proposed high-pressure Raman spectroscopy technique provides a new method to study bonding state,electronic structure,and phonon-electron coupling effects of metallic materials under high pressure.