中国物理B ›› 2011, Vol. 20 ›› Issue (2): 24208-024208.doi: 10.1088/1674-1056/20/2/024208
江斌1, 张冶金1, 周文君1, 陈微1, 刘安金1, 郑婉华2
Jiang Bin(江斌)a), Zhang Ye-Jin(张冶金) a), Zhou Wen-Jun(周文君)a), Chen Wei(陈微)a), Liu An-Jin(刘安金)a), and Zheng Wan-Hua(郑婉华)a)b)†
摘要: The local density of states (LDOS) of two-dimensional square lattice photonic crystal (PhC) defect cavity is studied. The results show that the LDOS in the centre is greatly reduced, while the LDOS at the point off the centre (for example, at the point (0.3a, 0.4a), where a is the lattice constant) is extremely enhanced. Further, the disordered radii are introduced to imitate the real devices fabricated in our experiment, and then we study the LDOS of PhC cavity with configurations of different disordered radii. The results show that in the disordered cavity, the LDOS in the centre is still greatly reduced, while the LDOS at the point (0.3a, 0.4a) is still extremely enhanced. It shows that the LDOS analysis is useful. When a laser is designed on the basis of the square lattice PhC rod cavity, in order to enhance the spontaneous emission, the active materials should not be inserted in the centre of the cavity, but located at positions off the centre. So LDOS method gives a guide to design the positions of the active materials (quantum dots) in the lasers.
中图分类号: (Resonators, cavities, amplifiers, arrays, and rings)