EFFECT OF FREE CARRIERS ON ZONE-CENTER VIBRATIONAL MODES IN HEAVILY DOPED P-TYPE SI .2. OPTICAL MODES
EFFECT OF FREE CARRIERS ON ZONE-CENTER VIBRATIONAL MODES IN HEAVILY DOPED P-TYPE SI .2. OPTICAL MODES
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DOI：
10.1103/physrevb.8.4734
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发表时间：
1973-01-01
影响因子：
3.7
通讯作者：
CARDONA, M
中科院分区：
文献类型：
--
作者：
CERDEIRA, F;FJELDLY, TA;CARDONA, M
利用拉曼散射研究了自由空穴对Si带心光学声子的影响。空穴的存在产生与单声子拉曼线重叠的价带间电子宽散射背景。这种重叠导致Fano型连续-离散干涉。通过改变（a）激光波长和（B）自由载流子浓度，可以改变所得到的Fano散射线的参数Γ和q。这些结果的理论解释的基础上详细的硅的价带结构和振动和电子的拉曼散射的共振特性。本文还研究了单轴应力对p型硅复合拉曼散射的影响。在大应力下，电子背景消失，声子线恢复本征材料的线宽。在中间应力范围内的行为是非常相似的声学声子在以前的文件中报告。
The effect of free holes on the optical phonons of Si at the zone center is investigated with Raman scattering. The presence of holes produces an inter-valence-band, electronic, broad, scattering background which overlaps with the one-phonon Raman line. This overlap results in a Fano-type continuous-discrete interference. The parameters Γ and q of the resulting Fano scattering line can be varied by changing (a) the laser wavelength and (b) the free-carrier concentration. A theoretical interpretation of these results based on the detailed valence-band structure of Si and on the resonant characteristics of the vibronic and electronic Raman scattering is presented. The effect of uniaxial stress on this composite Raman scattering of p-type Si is also investigated. At large stresses the electronic background disappears and the phonon lines recover the linewidths of the intrinsic material. The behavior in the intermediate-stress range is very similar to that reported for the acoustical phonons in the previous paper.