Xiao Zhi-Hong, Zheng Li, Lin HongZhen
International Laboratory for Adaptaive Bio-nanotechology, Suzhou Institute of Nano-tech and Nano-bionics (SINANO), Chinese Academy of Science, China.
Opt Express. 2012 Jan 16;20(2):1219-29. doi: 10.1364/OE.20.001219.
Photoinduced diffraction grating is theoretically investigated in a three-level ladder-type hybrid artificial molecule comprised of a semiconductor quantum dot (SQD) and a metal nanoparticle (MNP). The SQD and the MNP are coupled via the Coulomb interaction. The probe absorption vanishes under the action of a strong coupling field, indicating an effect of electromagnetically induced transparency (EIT). Based on this EIT effect, diffraction grating is achievable when a standing-wave coupling field is applied. It turns out that the efficiency of diffraction grating is greatly improved due to the existence of the MNP. Furthermore, the diffraction efficiency can be controlled by tuning the interaction strength between the SQD and the MNP. Nearly pure phase grating is obtained, showing high transmissivity and high diffraction efficiency up to 33%.
在由半导体量子点（SQD）和金属纳米颗粒（MNP）组成的三能级阶梯型混合人工分子中，对光致衍射光栅进行了理论研究。SQD和MNP通过库仑相互作用耦合。在强耦合场的作用下，探测吸收消失，这表明了电磁诱导透明（EIT）效应。基于这种EIT效应，当施加驻波耦合场时可实现衍射光栅。结果表明，由于MNP的存在，衍射光栅的效率得到了极大提高。此外，衍射效率可以通过调节SQD和MNP之间的相互作用强度来控制。获得了近乎纯的相位光栅，其具有高达33%的高透射率和高衍射效率。
