Liao Yun-Jhen, Cheng Chang-Wei, Wu Bao-Hsian, Wang Chun-Yuan, Chen Chih-Yen, Gwo Shangjr, Chen Lih-Juann
Department of Materials Science and Engineering, National Tsing Hua University Hsinchu Taiwan
Frontier Research Center on Fundamental and Applied Sciences of Matters, National Tsing Hua University Hsinchu Taiwan.
RSC Adv. 2019 May 2;9(24):13600-13607. doi: 10.1039/c9ra01484e. eCollection 2019 Apr 30.
ZnO is one of the most promising optical gain media and allows lasing in ZnO nanowires at room temperature. Plasmonic lasers are potentially useful in applications in biosensing, photonic circuits, and high-capacity signal processing. In this work, we combine ZnO nanowires and single-crystalline aluminum films to fabricate Fabry-Perot type surface plasmon polariton (SPP) lasers to overcome the diffraction limit of conventional optics. High quality ZnO nanowires were synthesized by a vapor phase transport process catalyzed growth. The ZnO nanowires were placed on a single-crystalline Al film grown by molecular beam epitaxy with an interlayer AlO deposited by atomic layer deposition. The plasmonic laser is of metal-oxide-semiconductor (MOS) structure, compatible with silicon device processing. An optimal thickness of atomic layer deposited AlO layer can lead to a low lasing threshold, 6.27 MW cm, which is 3 times and 12 times lower than that of previous reports for ZnO/Al and Zno/AlO/Al plasmonic lasers, respectively, owing to low materials loss. Both the thickness and quality of insulating layers were found to critically influence the lasing threshold of the SPP nanolasers in the subwavelength regime. The simulation results also manifest the importance of the quality of the dielectric interlayer.
氧化锌是最具前景的光学增益介质之一，能在室温下实现氧化锌纳米线中的激光发射。等离子体激光器在生物传感、光子电路和高容量信号处理等应用中具有潜在用途。在这项工作中，我们将氧化锌纳米线与单晶铝膜相结合，制造法布里 - 珀罗型表面等离子体激元（SPP）激光器，以克服传统光学的衍射极限。高质量的氧化锌纳米线通过气相输运过程催化生长合成。将氧化锌纳米线放置在通过分子束外延生长的单晶铝膜上，并通过原子层沉积沉积中间层氧化铝。该等离子体激光器具有金属 - 氧化物 - 半导体（MOS）结构，与硅器件工艺兼容。原子层沉积氧化铝层的最佳厚度可导致低激光阈值，为6.27兆瓦/平方厘米，分别比先前报道的氧化锌/铝和氧化锌/氧化铝/铝等离子体激光器低3倍和12倍，这归因于低材料损耗。发现绝缘层的厚度和质量在亚波长范围内对SPP纳米激光器的激光阈值有至关重要的影响。模拟结果也表明了介电中间层质量的重要性。
