Vertical optical ring resonators fully integrated with nanophotonic waveguides on silicon-on-insulator substrates

Abstract

Received Month X, XXXX; revised Month X, XXXX; accepted Month X, XXXX; posted Month X, XXXX (Doc. ID XXXXX); published Month X, XXXX We demonstrate full integration of vertical optical ring resonators with silicon nanophotonic waveguides on silicon-on-insulator substrates to accomplish a significant step towards 3D photonic integration. The on-chip integration is realized by rolling up 2D differentially strained TiO2 nanomembranes into 3D microtube cavities on a nanophotonic microchip. The integration configuration allows for out of plane optical coupling between the in-plane nanowaveguides and the vertical microtube cavities as a compact and mechanically stable optical unit, which could enable refined vertical light transfer in 3D stacks of multiple photonic layers. In this vertical transmission scheme, resonant filtering of optical signals at telecommunication wavelengths is demonstrated based on subwavelength thick walled microcavities. Moreover, an array of microtube cavities is prepared and each microtube cavity is integrated with multiple waveguides which opens up interesting perspectives towards parallel and multi-routing through a single cavity device as well as high-throughput optofluidic sensing schemes.

Localized Surface Plasmons Selectively Coupled to Resonant Light in Tubular Microcavities

“…Microtubular cavities are obtained by strain induced self-rolling of nanomembranes [17,18] which have previously received broad interest due to their unique properties including novel optical spin-orbit coupling phenomena [19], injection lasing [20], high opto-fluidic sensitivities [21], and compatibility with on-chip integration technologies [22,23]. This type of microcavity supports WGM resonances due to self-interference of light propagating along a circular ring trajectory defined by the tube cross section.…”

Label-Free Biological and Chemical Sensing Using Whispering Gallery Mode Optical Resonators: Past, Present, and Future

“…A partial list includes microrings [40,41], disks [12], knots/coils [42], bottles [43], droplets [44], goblets [45], rolled-up microcavities [46], bubbles [47], polystyrene microspheres [48,49], asymmetric cavities [50], cylinders [51], vertically coupled race track resonators [52], nearly spherical diamond resonators [53], crystalline CaF 2 cavities [54], and liquid-core optical ring resonators (LCORR) [55]. White-light WGM resonators have also been developed [56].…”

“…( a ) Vertical optical ring resonators. Adapted from [46]; ( b ) Knot resonators; ( c ) Microbubble resonators. Reprinted from [47], with the permission of AIP Publishing; ( d ) Polystyrene microsphere resonators.…”

Vertical integration of self-rolled-up microtube and silicon waveguides: a two-channel optical add–drop multiplexer

“…The rolling mechanism for the fabrication of the tubular shape of this structure facilitates the achievement of 3D light confinement in azimuthal, radial, and axial directions [9,10] . Furthermore, several experimental reports on the vertical coupling of this structure and other waveguides, both manually and monolithically, have been presented [11,12] . To the best of our knowledge, there has been no research conducted on designing passive SRM-based optoelectronic devices, particularly on an OADM, so far.…”