Department of Physics and Astronomy, The University of Western Ontario, London, Ontario, Canada N6A 3K7.
Nano Lett. 2011 Dec 14;11(12):5284-9. doi: 10.1021/nl2027348. Epub 2011 Nov 10.
We have studied the acousto-optic effect in polaritonic nanofibers made by embedding a cylindrical polaritonic nanowire within a photonic crystal. Here the nanowire consists of either a phonon-polaritonic or an exciton-polaritonic material. The nanowire is doped with ensemble of noninteracting quantum dots. Quantum dots interact with the nanofiber via the exciton-polariton interaction. It is found that for the certain acoustic strain intensity the nanofiber has a localized-to-delocalized polariton transition similar to the metal-to-insulator transitions in doped semiconductors. It is also found that nanofiber has a transparent state due to the exciton-bound polariton coupling. The transparent state can be switched ON or OFF by the external acoustic strain intensity. These are very useful discoveries that can be used to fabricate new types of polaritonic nanoswitches and nanosensors.
我们研究了在由嵌入光子晶体中的圆柱形极化子纳米线组成的极化子纳米纤维中的声光效应。这里的纳米线由声子极化子或激子极化子材料组成。纳米线掺杂有一组非相互作用的量子点。量子点通过激子极化激元相互作用与纳米纤维相互作用。结果发现，对于一定的声应变强度，纳米纤维具有类似于掺杂半导体中的金属-绝缘体转变的局域到离域极化激元转变。还发现，由于激子束缚极化激元耦合，纳米纤维具有透明状态。通过外部声应变强度可以打开或关闭透明状态。这些都是非常有用的发现，可以用来制造新型的极化子纳米开关和纳米传感器。
