Fig. 3
From: Hybrid tungsten oxyselenide/graphene electrodes for near-lossless 2D semiconductor phase modulators
Phase modulation for device with ITO, graphene, and TOS/graphene electrodes. a Schematic of the fabricated device structure, consisting of a capacitor stack (monolayer WS2/hBN/graphene/TOS) integrated onto a SiN microring resonator. Right top: Side-view schematic of the device, highlighting electrical contacts with the bottom WS2 layer and top graphene electrode, connected independently to gold electrodes for voltage biasing. Right bottom: Optical image of the actual device. b Top: schematic illustrating the on-resonance and off-resonance conditions within the microring-waveguide system. Bottom: Configuration for applying external electrical bias separately to the bottom WS2 and top TOS/graphene electrodes. c–e Top panels: Resonance spectra of microring resonators integrated with c ITO/hBN/WS2, d Gr/hBN/WS2, and e TOS/Gr/hBN/WS2 heterostructures, under varying applied bias voltages. Color intensity represents the amplitude of the transmission peaks, with spectral shifts indicating changes in the optical phase. Bottom panels: Corresponding line plots of the transmission spectra extracted from the top panels, highlighting the resonance wavelength shifts and changes in modulation behavior for each electrode configuration
