Center for Nanophotonics, FOM Institute for Atomic and Molecular Physics (AMOLF), Science Park 104, 1098 XG, Amsterdam, Netherlands.
Opt Lett. 2011 Apr 1;36(7):1170-2. doi: 10.1364/OL.36.001170.
We experimentally study the fields close to an interface between two photonic crystal waveguides that have different dispersion properties. After the transition from a waveguide in which the group velocity of light is v(g) ~ c/10 to a waveguide in which it is v(g) ~ c/100, we observe a gradual increase in the field intensity and the lateral spreading of the mode. We attribute this evolution to the existence of a weakly evanescent mode that exponentially decays away from the interface. We compare this to the situation where the transition between the waveguides only leads to a minor change in group velocity and show that, in that case, the evolution is absent. Furthermore, we apply novel numerical mode extraction techniques to confirm experimental results.
我们实验研究了具有不同色散特性的两个光子晶体波导之间界面附近的场。在从群速度 v(g)c/10 的波导过渡到群速度 v(g)c/100 的波导之后，我们观察到场强度逐渐增加和模式的横向扩展。我们将这种演化归因于存在一个弱消逝模式，它从界面呈指数衰减。我们将这种情况与波导之间的过渡只导致群速度略有变化的情况进行了比较，并表明在这种情况下，这种演化是不存在的。此外，我们应用新的数值模式提取技术来验证实验结果。
