Extremely small multimode interference couplers and ultrashort bends on InP by deep etching

Author

Spiekman, L.H. ; Oei, Y.S. ; Metaal, E.G. ; Green, F.H. ; Moerman, I. ; Smit, M.K.

Author_Institution

Dept. of Electr. Eng., Delft Univ. of Technol., Netherlands

Volume

6

Issue

8

fYear

1994

Firstpage

1008

Lastpage

1010

Abstract

We realized the smallest integrated optical multimode interference (MMI) couplers to date by etching through the quaternary guiding layer, maximizing the lateral index contrast, and thus obtaining a sufficient number of guided modes for proper operation despite the small size. Results include a 107 μm long 3 dB coupler with 0.9 dB excess loss and 0.2 dB unbalance, and a 216 μm long cross coupler with 2.0 dB excess loss and -28 dB crosstalk (TE). We also succeeded in making waveguide bends with a record bending radius of only 30 μm and negligible radiation loss.

Keywords

III-V semiconductors; bending; crosstalk; etching; indium compounds; integrated optics; optical couplers; optical losses; optical waveguides; 0.9 dB; 107 mum; 2 dB; 216 mum; InP; bending radius; cross coupler; crosstalk; deep etching; excess loss; guided modes; integrated optical multimode interference couplers; lateral index contrast; negligible radiation loss; quaternary guiding layer; small multimode interference couplers; small size; ultrashort bends; waveguide bends; Couplers; Etching; Indium phosphide; Interference; Optical crosstalk; Optical interferometry; Optical losses; Optical receivers; Optical sensors; Optical waveguides;

fLanguage

English

Journal_Title

Photonics Technology Letters, IEEE

Publisher

ieee

ISSN

1041-1135

Type

jour

DOI

10.1109/68.313078

Filename

313078