title: A 2-to-4 decoder switch in SiGe/Si multimode inteference.
abstract: Based on multimode interference principle and free-carrier plasma dispersion effect, a SiGe/Si 2-to-4 decoder switch is proposed and simulated. The decoder switch consists of two input single-mode ridge waveguides, a multimode interference section, and four output single-mode ridge waveguides. In the multimode interference section, two index-modulation regions are introduced. Design principle of the decoder switch is described and the device characteristics are demonstrated theoretically by beam propagation method. Simulated results show that the insertion loss of the decoder switch is less than 0.36 dB and the crosstalk is less than -19.7 dB. The device can divert input optical signals to any one of the four output waveguides when a forward bias voltage is applied to the two index-modulation regions.
authors.forename: Zhiwen
authors.initials: Z
authors.lastname: Chen
authors.forename: Zhangjian
authors.initials: Z
authors.lastname: Li
authors.forename: Baojun
authors.initials: B
authors.lastname: Li