Nonlinear optical waveguides based on nearinfrared intersubband transitions in GaN/AIN quantum wells

作     者：Li, Yan Bhattacharyya, Anirban Thomidis, Christos Moustakas, Theodore D. Paiella, Roberto 

作者机构：Boston Univ Dept Elect & Comp Engn Boston MA 02215 USA Boston Univ Photon Ctr Boston MA 02215 USA 

出 版 物：《OPTICS EXPRESS》 (Opt. Express)

年 卷 期：2007年第15卷第9期

页      面：5860-5865页

核心收录：

学科分类：070207[理学-光学] 07[理学] 08[工学] 0803[工学-光学工程] 0702[理学-物理学] 

主　　题：All optical signal processing Fiber networks Fiber optic communications Nonlinear optical waveguides Quantum cascade semiconductor lasers Quantum wells 

摘      要：We present the design, fabrication, and characterization of III-nitride quantum-well waveguides optimized for nonlinear-optical switching via intersubband transitions. A dielectric structure consisting of an AlN lower cladding and a GaN cap layer allows minimizing the propagation losses while maintaining a large modal overlap with the quantum-well active layer. A strong nonlinear saturation of the intersubband absorption near 1.55 mu m is demonstrated at record low input powers for these materials;in particular, a 3-dB saturation pulse energy of less than 10 pJ with 240-fs pulses is measured. Combined with the well established sub-picosecond recovery lifetimes of intersubband absorption in III-nitride quantum wells, these results are very promising for all-optical switching applications in future ultrafast fiber-optic communication networks. (c) 2007 Optical Society of America