Modal characterization of nanophotonic waveguides for atom trapping

作     者：Stievater, Todd H. Kozak, Dmitry A. Pruessner, Marcel W. Mahon, Rita Park, Doewon Rabinovich, William S. Fatemi, Fredrik K. 

作者机构：US Naval Res Lab Washington DC 20375 USA US Army Res Lab Adelphi MD 20783 USA 

出 版 物：《OPTICAL MATERIALS EXPRESS》 (光学材料快讯)

年 卷 期：2016年第6卷第12期

页      面：3826-3837页

核心收录：

学科分类：070207[理学-光学] 07[理学] 08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0803[工学-光学工程] 0702[理学-物理学] 

基　　金：Office of Naval Research Army Research Laboratory 

主　　题：Atom optics Guided waves Waveguides Nanophotonics and photonic crystals 

摘      要：Nanophotonic waveguides are a promising platform to trap cold atoms using red-and blue-detuned evanescent-field optical dipole forces. The asymmetric structure of integrated waveguides leads to a large birefringence that is not encountered in cylindrically symmetric optical nanofibers. We have studied both theoretically and experimentally the modal properties and suitability of silicon nitride rib waveguides for cold-atom trapping. The dependence of the modal effective index on the rib width is explored experimentally by measuring beat lengths between propagating modes. These measurements are made using a novel spatial Fourier analysis technique based on conventional far-field imaging of elastic scattering from the waveguide. We find that the beat length between the lowest order TE00 and TM00 modes is approximately 5 mu m, in excellent agreement with numerical calculations. We propose to take advantage of this birefringence and mode structure to create novel, one-dimensional periodic trapping potentials for atoms within the evanescent field of the waveguide. (C) 2016 Optical Society of America