We propose a novel photonic circuit element configuration that emulates the throughport response of a bus coupled travelingwave resonator using two standingwave resonant cavities. In this “reflectionless resonator unit”, the two constituent cavities, here photonic crystal (PhC) nanobeams, exhibit opposite mode symmetries and may otherwise belong to a single design family. They are coupled evanescently to the bus waveguide without mutual coupling. We show theoretically, and verify using FDTD simulations, that reflection is eliminated when the two cavities are wavelength aligned. This occurs due to symmetryinduced destructive interference at the bus coupling region in the proposed photonic circuit topology. The transmission is equivalent to that of a buscoupled travelingwave (e.g. microring) resonator for all coupling conditions. We experimentally demonstrate an implementation fabricated in a new 45 nm silicononinsulator complementary metaloxide semiconductor (SOI CMOS) electronicphotonic process. Both PhC nanobeam cavities have a fullwidth halfmaximum (FWHM) mode length of 4.28
 Award ID(s):
 1743235
 Publication Date:
 NSFPAR ID:
 10292812
 Journal Name:
 Nanophotonics
 Volume:
 10
 Issue:
 1
 Page Range or eLocationID:
 343 to 360
 ISSN:
 21928606
 Sponsoring Org:
 National Science Foundation
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