Experimental Study of the Solid State Vibrational Laser

最近对晶体中cn离子的随时间振动和旋转响应的红外实验表明，这种双原子分子在固体中的振动动力学导致了意想不到的激光行为。如果晶体中的其他双原子缺陷具有与CN-相关的性质，那么固态振动激光器在红外和远红外光谱区域的各种应用都是实用的。一个基本的实验问题是近红外色中心激光泵浦与可以掺杂到晶体中的分子的泛音频率之间缺乏一致性。PI发现非共振紫外激光辐射可以用来泵浦CN-的振动流形，这为研究固体分子的红外辐射特性开辟了另一条途径。将脉冲紫外准分子激光器与超高分辨率傅里叶变换红外光谱仪相结合，将提供一种新型高效的时间分辨振动光谱，可用于研究固态分子的多能级红外能量传递。对于具有亚秒弛豫时间的复杂分子的检测，傅里叶变换红外光谱仪将以不同的模式对皮秒脉冲之间的延迟进行时间分析，以测量非谐波振动器中的快速饱和吸收。

Recent IR experiments on the time dependent vibrational and rotational response of CN-ions in crystals indicate that the vibrational dynamics of this diatomic molecule in solids leads to unexpected lasing behavior. If other diatomic defects in crystals have properties related to CN- then solid state vibrational lasers could be practical for a variety of applications in the infrared and far-infrared spectral regions. One fundamental experimental problem has been the lack of coincidences between near-IR color center laser pumps and the overtone frequencies of molecules which can be doped into crystals. The discovery by the PI that nonresonant UV laser radiation can be used to pump the vibrational manifold of CN- opens up another avenue through which the IR radiative properties of molecules in solids can be studied. The interfacing of a pulsed UV excimer laser to an ultrahigh resolution fourier-transform infrared spectrometer will provide a new efficient type of time resolved vibrational spectroscopy which can be used to explore multilevel IR energy transfer of molecules in the solid state. For the examination of complex molecules with subnsecond relaxation times the fourier- transform infrared spectrometer will be used in a different mode to time analyze the delay between picosecond pulses in the measurement of fast saturable absorption in the anharmonic vibrator.