采用密度泛函理论平面波赝势法研究了氢杂质位于氢终止金刚石薄膜亚表面层中三种不同位点处时金刚石的结构变化，以及氢原子在三种金刚石薄膜表面上的吸附难易程度，并对表面活化反应进行了过渡态搜索以探究化学气相沉积(CVD)过程中金刚石薄膜亚表面层氢杂质对表面活化的影响。对比计算结果发现：生长过程中，亚表面层的氢杂质使其附近的金刚石结构产生了畸变，同时金刚石表面结构会对畸变程度产生影响。氢原子在含有氢杂质的三种金刚石薄膜上的吸附能与理想金刚石薄膜差异很小，但发生萃取反应产生活性位点的能垒比理想金刚石薄膜更低，这与亚表面层中的氢杂质使金刚石薄膜具有P型半导体特征这一现象有关。这一结果说明富氢反应气氛有利于活性位点的产生并以更高速率进行生长。

We present a novel design of a compact, stable, and easy-adjustable semiconductor optical amplifier (SOA) system. This SOA system is capable of providing up to 560-mW laser power at the wavelength of 852 nm. For the continuous-wave (CW) seeding laser, the amplification gain can reach 18 dB. We add amplitude modulation onto the CW laser and measure the modulation amplification between seeding and output laser. The amplification gain remains constant within the frequency range from 10 Hz to 1 MHz. The whole system could work in ultra-stable condition: for CW seeding laser, the fluctuation of output power is less than 0.33% in several hours.