Pérez-Sánchez F L, Pérez-Rodríguez F
Escuela de Ciencias, Universidad Autónoma 'Benito Juárez' de Oaxaca, Avenida Universidad S/N, Ex-Hacienda de Cinco Señores, Ciudad Universitaria, Oaxaca de Juárez, Oaxaca, 68120, Mexico.
J Phys Condens Matter. 2009 Sep 2;21(35):355010. doi: 10.1088/0953-8984/21/35/355010. Epub 2009 Aug 10.
The photon-phonon coupling at C(001)-(2 × 1) surfaces and its manifestation in far-infrared reflectance anisotropy spectra (FIR-RAS) are theoretically investigated. We solve the coupled system of equations for the electromagnetic field and lattice vibrations, described within the adiabatic bond charge model (ABCM), with the method of expansion into bulk phonon and photon modes. The calculated FIR-RAS exhibit resonances associated with zone-center surface phonons in good agreement with available HREELS experiments and predictions of vibrational modes for diamond (001)-(2 × 1) surfaces from ABCM and ab initio calculations. Interestingly, the reflectance anisotropy spectra for a C(001)-(2 × 1) surface turn out to be qualitatively different from the spectra for a Si(001)-(2 × 1) surface, reported previously.
从理论上研究了C(001)-(2×1)表面的光子-声子耦合及其在远红外反射各向异性光谱（FIR-RAS）中的表现。我们采用向体声子和光子模式展开的方法，求解了绝热键电荷模型（ABCM）中描述的电磁场和晶格振动的耦合方程组。计算得到的FIR-RAS显示出与区中心表面声子相关的共振，这与现有的高分辨电子能量损失谱（HREELS）实验以及ABCM和从头算计算得出的金刚石(001)-(2×1)表面振动模式预测结果吻合良好。有趣的是，结果表明C(001)-(2×1)表面的反射各向异性光谱与之前报道的Si(001)-(2×1)表面的光谱在性质上有所不同。
