title: Facet-rotated echelle grating for cyclic wavelength router with uniform loss and flat passband.
abstract: A novel method for designing a cyclic echelle grating wavelength router with uniform loss and flat passband is proposed and experimentally demonstrated. A 4×4 cyclic wavelength router with a channel spacing of 400 GHz at 1550 nm wavelength band is designed and fabricated in InP. Measurement results show that the loss of 16 input-output combinations varies from 9 to 19.3 dB in a conventional design, with a nonuniformity of 10.3 dB, while the 1-dB spectral bandwidth is only 0.3 nm. By rotating angles of grating facets according to an appropriately designed distribution function, the loss nonuniformity is reduced to 1.5 dB, and a flat-top spectral response with 1 dB bandwidth of 1.0 nm is achieved simultaneously.
authors.forename: Ge
authors.initials: G
authors.lastname: Mu
authors.forename: Pingli
authors.initials: P
authors.lastname: Huang
authors.forename: Lin
authors.initials: L
authors.lastname: Wu
authors.forename: Jian-Jun
authors.initials: JJ
authors.lastname: He