Department of Physics and Meteorology, Indian Institute of Technology Kharagpur, Kharagpur, India.
Nanotechnology. 2012 Feb 17;23(6):065702. doi: 10.1088/0957-4484/23/6/065702. Epub 2012 Jan 17.
We have fabricated Er doped germanium nanowires of different diameters by pulsed laser deposition and chemical methods. Er induced photoluminescence emission due to the intra-4f (4)I(13/2)→(4)I(15/2) transition of Er energy levels at 1.53 µm has been achieved at room temperature using both resonant (980 nm) and non-resonant (325 nm) excitation of Er ions. The observed 1.53 µm photoluminescence signal upon non-resonant 325 nm excitation is attributed to the Ge related oxygen deficiency centers surrounding the Ge core. For direct excitation, the infrared photoluminescence characteristics have been studied as a function of Er concentration, photon flux, and diameter of the nanowires. The Er related emission signal is found to be enhanced with increase in Er concentration, pump flux of 980 nm, and the nanowire diameter. The time resolved characteristics of the Er induced emission peak have been studied as a function of the pump flux as well as the diameter of the Ge nanowires.
我们通过脉冲激光沉积和化学方法制备了不同直径的掺铒锗纳米线。室温下，通过铒离子的共振（980nm）和非共振（325nm）激发，实现了铒能级的内 4f（4）I（13/2）→（4）I（15/2）跃迁引起的 1.53μm 光致发光发射。在非共振 325nm 激发下观察到的 1.53μm 光致发光信号归因于锗核周围与锗有关的氧空位中心。对于直接激发，研究了红外光致发光特性作为 Er 浓度、光子通量和纳米线直径的函数。发现 Er 相关发射信号随着 Er 浓度、980nm 泵浦通量和纳米线直径的增加而增强。还研究了 Er 诱导发射峰的时间分辨特性作为泵浦通量和 Ge 纳米线直径的函数。
