title: Wavelength independent multimode interference coupler.
abstract: We propose an ultra-broadband multimode interference (MMI) coupler with a wavelength range exceeding the O, E, S, C, L and U optical communication bands. For the first time, the dispersion property of the MMI section is engineered using a subwavelength grating structure to mitigate wavelength dependence of the device. We present a 2 × 2 MMI design with a bandwidth of 450nm, an almost fivefold enhancement compared to conventional designs, maintaining insertion loss, power imbalance and MMI phase deviation below 1dB, 0.6dB and 3°, respectively. The design is performed using an in-house tool based on the 2D Fourier Eigenmode Expansion Method (F-EEM) and verified with a 3D Finite Difference Time Domain (FDTD) simulator.
authors.affiliation: Departamento de Ingeniería de Comunicaciones, ETSI Telecomunicación, Universidad de Málaga, 29010 Málaga, Spain. amaesen@ic.uma.es
authors.forename: A
authors.initials: A
authors.lastname: Maese-Novo
authors.forename: R
authors.initials: R
authors.lastname: Halir
authors.forename: S
authors.initials: S
authors.lastname: Romero-García
authors.forename: D
authors.initials: D
authors.lastname: Pérez-Galacho
authors.forename: L
authors.initials: L
authors.lastname: Zavargo-Peche
authors.forename: A
authors.initials: A
authors.lastname: Ortega-Moñux
authors.forename: I
authors.initials: I
authors.lastname: Molina-Fernández
authors.forename: J G
authors.initials: JG
authors.lastname: Wangüemert-Pérez
authors.forename: P
authors.initials: P
authors.lastname: Cheben
mesh_terms: D017076:Computer-Aided Design; D004867:Equipment Design; D019544:Equipment Failure Analysis; D012031:Refractometry / Q000295:instrumentation*; D020349:Surface Plasmon Resonance / Q000295:instrumentation*; D013685:Telecommunications / Q000295:instrumentation*