Marušić L, Despoja V, Sunjić M
J Phys Condens Matter. 2006 May 3;18(17):4253-63. doi: 10.1088/0953-8984/18/17/013. Epub 2006 Apr 13.
Surface excitation spectra are calculated, including both collective and single-particle modes, and examined in detail. This is achieved by calculating the non-local dielectric function ε(p)(Q,z,z('),ω) of the thin jellium film within the random phase approximation (RPA) (using local density approximation wavefunctions which actually takes us beyond the RPA), from which we then derive the spectral function. The high precision of the calculations enables us to analyse not only the collective (surface plasmon) modes and their dependence on the film thickness, but also the intra-band electron-hole excitations, and for the first time oscillatory structures due to inter-band transitions. The spectra are then analysed with special attention to their dependence on the slab thickness, and the periodic peaks observed due to single-particle excitations in the spectra.
计算了包括集体模式和单粒子模式在内的表面激发光谱，并进行了详细研究。这是通过在随机相位近似（RPA）内计算薄电子气膜的非局域介电函数ε(p)(Q,z,z('),ω)来实现的（使用局部密度近似波函数，这实际上使我们超越了RPA），然后从中导出光谱函数。计算的高精度使我们不仅能够分析集体（表面等离子体激元）模式及其对膜厚度的依赖性，还能分析带内电子-空穴激发，并且首次分析了由于带间跃迁引起的振荡结构。然后对光谱进行分析，特别关注它们对平板厚度的依赖性，以及光谱中由于单粒子激发而观察到的周期性峰值。
