We propose a three-dimensional waveguide structure for the realization of mode-selective switches. where the high-order spatial modes of a few-mode waveguide can be switched to various single-mode waveguides with thermo-optically controlled vertical asymmetrical directional couplers. To demonstrate the idea. we design and fabricate two specific devices with a polymer material for a wa... https://www.lightemupsequences.com/flash-pick-Tiki-Luau-Shaped-Thank-You-Cards-Tropical-Hawaiian-Summer-Party-Thank-You-Note-Cards-with-Envelopes-Set-of-12-top-super