Design of a High-efficiency Fiber-to-chip Coupler with Reflectors

  • Yoo, Keon ;
  • Lee, Jong-Ho
  • Received : 2016.03.08
  • Accepted : 2016.04.18
  • Published : 2016.04.30


In this paper, an inversely tapered coupler with Bragg reflectors is reported for the first time. With appropriately positioned reflecting structures, our fiber-to-chip coupler can more efficiently transmit the light from fiber to a waveguide in a photonic integrated circuit (PIC). A numerical simulation evaluated the coupler's efficiency with the reflector. Optimized parameters that maximize the efficiency of the coupler are also investigated. Simulation results show that the reflector with appropriate parameters enhances efficiency by up to 7 dB. Likewise, Bragg metal reflectors implemented by the conventional metallization process can also improve efficiency. It is also shown that the proposed reflector enhances the coupling efficiency in a double-tip taper coupler.


Silicon nanophotonics;Coupler;Reflector;Design


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Supported by : Ministry of Science, ICT & Future Planning