The physical principles of terahertz silicon lasers based on intracenter transitions
The physical principles of terahertz silicon lasers based on intracenter transitions
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基于中心跃迁的太赫兹硅激光器物理原理
DOI：
10.1002/pssb.201248322
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发表时间：
2013
期刊：
影响因子：
--
通讯作者：
H. Hübers
中科院分区：
文献类型：
--
作者：
S. Pavlov;R. Zhukavin;V. Shastin;H. Hübers
2000年报道了第一台硅激光器。它基于单晶硅中类氢磷施主的杂质跃迁。从那时起，基于硅中其他V族施主的几种激光器已经被证明。这些激光器在中红外激光器的光泵浦下在低晶格温度下工作，并在50至230 µm（1.2至6.9 THz）范围内发射离散波长的光。V族替代施主的特定激发态之间的偶极允许的光学跃迁用于施主型太赫兹（THz）硅激光器。粒子数反转是由于杂质原子的特定电子-声子相互作用而实现的。这导致供体中心的长寿命和短寿命激发态。另一种类型的THz激光器利用通过拉曼-活性中心内电子跃迁的光子的受激共振拉曼-型散射。通过改变泵浦激光器频率，拉曼中心内硅激光器的频率可以在至少4.5和6.4 THz之间连续变化。施主和拉曼-型太赫兹硅激光器的增益是0.5到10 cm-1的量级，这与太赫兹量子级联激光器和红外拉曼硅激光器中实现的净增益相似。此外，激光过程的基本方面提供了新的信息的特点，电子捕获浅杂质中心在硅中，非平衡载流子的激发杂质态的寿命，和电子-声子相互作用。
The first silicon laser was reported in the year 2000. It is based on impurity transitions of the hydrogen‐like phosphorus donor in monocrystalline silicon. Several lasers based on other group‐V donors in silicon have been demonstrated since then. These lasers operate at low lattice temperatures under optical pumping by a midinfrared laser and emit light at discrete wavelengths in the range from 50 to 230 µm (between 1.2 and 6.9 THz). Dipole‐allowed optical transitions between particular excited states of group‐V substitutional donors are utilized for donor‐type terahertz (THz) silicon lasers. Population inversion is achieved due to specific electron–phonon interactions of the impurity atom. This results in long‐living and short‐living excited states of the donor centers. Another type of THz laser utilizes stimulated resonant Raman‐type scattering of photons by a Raman‐active intracenter electronic transition. By varying the pump‐laser frequency, the frequency of the Raman intracenter silicon laser can be continuously changed between at least 4.5 and 6.4 THz. The gain of the donor and Raman‐type THz silicon lasers is of the order of 0.5 to 10 cm−1, which is similar to the net gain realized in THz quantum cascade lasers and infrared Raman silicon lasers. In addition, fundamental aspects of the laser process provide new information about the peculiarities of electronic capture by shallow impurity centers in silicon, lifetimes of nonequilibrium carriers in excited impurity states, and electron–phonon interaction.