Abstract

An analysis of multimode waveguides where several modes are coupled via quasiperiodic perturbations is presented. The supermodes (or eigenmodes) of the structure are derived and orthonormality considerations are discussed. In addition, a new type of mode converter between copropagating modes is proposed, where mode conversion is mediated by a backward-propagating mode. Adiabatic and nonadiabatic coupling coefficients are considered and the supermode formalism is used to conveniently describe the mode of operation of the device.

[IEEE ]

Broad bandwidth waveguide polarizer via grating mediated mode conversion

Jun Zheng, Zhi-Cheng Ye, Cheng-Liang Wang, Yi-Fei Fu, and Zheng-Ming Sheng
J. Opt. Soc. Am. B 36(6) 1602-1606 (2019)

Investigation of backward cladding-mode coupling in Bragg gratings implemented on a Si₃N₄ waveguide platform

Jiahao Zhan, Yang Zhang, Yiwen Hu, Shengjie Xie, Sylvain Veilleux, and Mario Dagenais
J. Opt. Soc. Am. B 36(12) 3442-3449 (2019)

Mode conversion using optical analogy of shortcut to adiabatic passage in engineered multimode waveguides

Tzung-Yi Lin, Fu-Chen Hsiao, Yao-Wun Jhang, Chieh Hu, and Shuo-Yen Tseng
Opt. Express 20(21) 24085-24092 (2012)

Analysis of grating-assisted backward coupling employing the unified coupled-mode formalism

Nahum Izhaky and Amos Hardy
J. Opt. Soc. Am. A 16(6) 1303-1311 (1999)

Demonstration of mode conversion using anti-symmetric waveguide Bragg gratings

Jose M. Castro, David F. Geraghty, Seppo Honkanen, Christoph M. Greiner, Dmitri Iazikov, and Thomas W. Mossberg
Opt. Express 13(11) 4180-4184 (2005)