Ustün Kadir, Kurt Hamza
Department of Electrical and Electronics Engineering, TOBB University of Economics and Technology, Ankara, 06560, Turkey.
Opt Express. 2010 Sep 27;18(20):21155-61. doi: 10.1364/OE.18.021155.
We explore slow light behavior of a specially designed optical waveguide by carrying out structural dispersion using numerical techniques. The structure proposed is composed of square-lattice photonic crystal waveguide integrated with side-coupled cavities. We report three orders of magnitude reduction in group velocity at around υ(g) ≅ 0.0008c with strongly suppressed group velocity dispersion. The analysis is performed by using both plane-wave expansion and finite-difference time-domain methods. For the first time, we succeeded to show such a low group velocity in photonic structures. Slow light pulse propagation accompanied by light tunneling between each cavity is observed. These achievements show the feasibility of photonic devices to generate extremely large group index which in turn will eventually pave the way to new frontiers in nonlinear optics, optical buffers and low threshold lasers.
我们通过使用数值技术进行结构色散来探索一种特殊设计的光波导的慢光行为。所提出的结构由与侧面耦合腔集成的方形晶格光子晶体波导组成。我们报告了在群速度约为υ(g)≅0.0008c时群速度降低了三个数量级，且群速度色散得到了强烈抑制。分析是通过平面波展开法和时域有限差分法进行的。我们首次成功地在光子结构中展示了如此低的群速度。观察到了慢光脉冲传播以及每个腔之间的光隧穿现象。这些成果表明了光子器件产生极大群折射率的可行性，这反过来最终将为非线性光学、光缓冲器和低阈值激光器等新领域铺平道路。
