Graphene-integrated microtube whispering-gallery mode resonators for polarization-sensitive optical modulation and photodetection.

The monolithic photonic-electronic integration is crucial for high-bandwidth optical communication and computing, while existing structures struggle to reconcile compact footprints with performance preservation. Here, graphene-integrated silicon nitride microtube whispering-gallery mode resonators, fabricated via wafer-level nanomembrane self-rolling process, are demonstrated for polarization optical modulation and photodetection in photonic-electronic synergy. The engineered lobe-shaped architecture in the microtube facilitates axial mode quantization, greatly enhancing the optical mode confinement and improving the quality factor. A balanced trade-off between photodetection efficiency and optical resonance is achieved by adjusting the coupling between graphene and microtube resonance, and graphene-integrated microtube resonators with lobe structure demonstrate an efficient optical resonance ( Q  = 2008.36) and high photoresponsivity (2.80 A W-1). Furthermore, fourfold rotational symmetry breaking in microtubes presents a workable structural paradigm for the polarization-sensitive optical modulation and photodetection, overall characteristics presents a promising platform for optical manipulation and multidimensional detection of integrated photonic and optoelectronic systems.