中国物理B ›› 2007, Vol. 16 ›› Issue (7): 2015-2022.doi: 10.1088/1009-1963/16/7/035

• CLASSICAL AREAS OF PHENOMENOLOGY • 上一篇    下一篇

Semi-vectorial analysis of a compact wavelength demultiplexer based on the tapered multimode interference coupler

肖金标, 刘旭, 蔡纯, 孙小菡   

  1. Lab of Photonics and Optical Communications, Electronic Engineering Department, Southeast University, Nanjing 210096, China
  • 收稿日期:2006-06-26 修回日期:2007-01-11 出版日期:2007-07-04 发布日期:2007-07-04
  • 基金资助:
    Project supported by the Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant No 20060286042).

Semi-vectorial analysis of a compact wavelength demultiplexer based on the tapered multimode interference coupler

Xiao Jin-Biao(肖金标), Liu Xu(刘旭), Cai Chun(蔡纯), and Sun Xiao-Han(孙小菡)   

  1. Lab of Photonics and Optical Communications, Electronic Engineering Department, Southeast University, Nanjing 210096, China
  • Received:2006-06-26 Revised:2007-01-11 Online:2007-07-04 Published:2007-07-04
  • Supported by:
    Project supported by the Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant No 20060286042).

摘要: Based on a parabolically tapered multimode interference (MMI) coupler with a deep-etched SiO2/SiON rib waveguide, a compact wavelength demultiplexer operating at 1.30 and 1.55\mum wavelengths is proposed and analysed by using three-dimensional semi-vectorial finite-difference beam propagation method (3D-SV-FD-BPM). The results show that a MMI section of 330.0\mum in length, which is only 76% length of a straight MMI coupler, is achieved with the contrasts of 42.3 and 39.2dB in quasi-TE mode, and 38.4 and 37.8dB in quasi-TM mode at wavelengths 1.30 and 1.55\mum, respectively, and the insertion losses below 0.2dB at both wavelengths and in both polarization states. The alternating direction implicit algorithm with the Crank--Nicholson scheme is applied to the discretization of the 3D-SV-FD-BPM formulation along the longitudinal direction. Moreover, a modified FD scheme is constructed to approximate the resulting equations along the transverse directions, in which the discontinuities of the derivatives of magnetic field components Hy and Hx along the vertical and horizontal interfaces, respectively, are involved.

Abstract: Based on a parabolically tapered multimode interference (MMI) coupler with a deep-etched SiO2/SiON rib waveguide, a compact wavelength demultiplexer operating at 1.30 and 1.55\mum wavelengths is proposed and analysed by using three-dimensional semi-vectorial finite-difference beam propagation method (3D-SV-FD-BPM). The results show that a MMI section of 330.0\mum in length, which is only 76% length of a straight MMI coupler, is achieved with the contrasts of 42.3 and 39.2dB in quasi-TE mode, and 38.4 and 37.8dB in quasi-TM mode at wavelengths 1.30 and 1.55\mum, respectively, and the insertion losses below 0.2dB at both wavelengths and in both polarization states. The alternating direction implicit algorithm with the Crank--Nicholson scheme is applied to the discretization of the 3D-SV-FD-BPM formulation along the longitudinal direction. Moreover, a modified FD scheme is constructed to approximate the resulting equations along the transverse directions, in which the discontinuities of the derivatives of magnetic field components Hy and Hx along the vertical and horizontal interfaces, respectively, are involved.

Key words: wavelength demultiplexer, multimode interference, beam propagation method, photonic integrated circuits

中图分类号:  (Optical communication systems, multiplexers, and demultiplexers?)

  • 42.79.Sz
02.10.Yn (Matrix theory) 02.70.Bf (Finite-difference methods) 42.82.Et (Waveguides, couplers, and arrays)