Cui Ni, Gan Ziyang, Zhang Lida
Siyuan Laboratory, Guangzhou Key Laboratory of Vacuum Coating Technologies and New Energy Materials, Department of Physics, Jinan University, Guangzhou, 510632, China.
Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Jinan University, Guangzhou, 510632, China.
Sci Rep. 2017 Oct 27;7(1):14198. doi: 10.1038/s41598-017-14456-z.
We propose a novel scheme to realize an optical waveguide induced by an active Raman gain (ARG) process in a four-level N-type atomic system. Because of the nature of the ARG, there are two distinct features related to the waveguide: i) It is not absorptive, on the contrary, weak gain is presented; ii) It can be improved by the Doppler effect in the sense that the dispersion is enhanced while the gain is further reduced. This is in sharp contrast to the previously considered schemes where usually the optical induced waveguide is passive and is severely attenuated by the Doppler effect. We then study the paraxial light propagation in the waveguide which shows that the propagation dynamics is lossless and diffractionless.
我们提出了一种新颖的方案，以在四能级N型原子系统中实现由有源拉曼增益（ARG）过程诱导的光波导。由于ARG的特性，与该波导相关有两个明显的特征：i）它不是吸收性的，相反，呈现出微弱的增益；ii）从色散增强而增益进一步降低的意义上来说，它可以通过多普勒效应得到改善。这与之前考虑的方案形成了鲜明对比，在之前的方案中，通常光诱导波导是无源的，并且会被多普勒效应严重衰减。然后我们研究了光波在该波导中的傍轴传播，结果表明传播动力学是无损且无衍射的。
