Ramírez M O, Jaque D, Bausá L E, García Solé J, Kaminskii A A
Departamento de Física de Materiales, C-IV, Facultad de Ciencias, Universidad Autónoma de Madrid, Spain.
Phys Rev Lett. 2005 Dec 31;95(26):267401. doi: 10.1103/PhysRevLett.95.267401. Epub 2005 Dec 19.
In this Letter we have used the optical pump induced thermal loading to drive Nd(3+) a doped Sr(0,47)Ba(0.53)(Nb)(3))(2) laser crystal during laser operation through its ferroelectric phase transition. We demonstrate that lasing is possible below, at, and above phase transition. For temperatures close to (approximately 105 degrees C) the spatial distribution of laser radiation is remarkably affected. This feature, which leads to a laser gain depression, can be explained in terms of the strong temperature dependence of the thermo-optic coefficient during phase transition. Additionally, the visible radiation generated by intracavity self-frequency doubling disappears when the phase transition is undergone, showing a bistable behavior. The results provide fundamental information on physical parameters along the phase transition and will stimulate further work in the fields of nonlinear optics, optical switching, and data storage.
在本信函中，我们利用光泵浦诱导热负载，在激光运转期间通过铁电相变驱动掺Nd(3+)的Sr(0.47)Ba(0.53)(NbO3)2激光晶体。我们证明了在相变温度以下、相变温度处及相变温度以上都有可能实现激光发射。对于接近（约105℃）相变温度的情况，激光辐射的空间分布会受到显著影响。这一导致激光增益降低的特性，可以根据相变期间热光系数对温度的强烈依赖性来解释。此外，腔内自倍频产生的可见辐射在经历相变时会消失，呈现出双稳态行为。这些结果提供了沿相变过程物理参数的基本信息，并将推动非线性光学、光开关和数据存储领域的进一步研究。
