Fig. 5

1D solid-state microstructures for electrically controllable optical waveguides. a Schematic of an organic field-effect optical waveguide (OFEW). b FM image of the CHICZ crystal ribbons with a scale bar of 50 μm. c Current transport is parallel with the optical waveguide direction in mode I. Scale bar: 20 μm. d Laser in and laser out of the devices working in mode I. e-f Working in mode I. Optical waveguide modulation on field-effect performance, the plot of PL intensity dependence on gate voltage e, the plot of PL intensity dependence on source–drain voltage f. g-h Transfer characteristic dependence on a different laser illumination working in mode I g, and mode II h, respectively. i Schematic depiction of the asymmetric optical waveguide in BPEA nanowires under an electric field. j The optical waveguide asymmetric power propagation under the electric field. k The white circles mark the optical waveguide intensity from the microwire end tip without and with forward and backward electric fields (1.0 × 10⁶ V/m), respectively. Scale bar: 10 μm. l Corresponding outcoupled PL spectra collected from the end tips of the microwire. m Schematic of the exciton diffusion in the absence and presence of an external electric field. n Schematic depiction of the spatial relationship between BPEA molecular transition dipole moment (blue arrows) and the growth direction (red arrow) of the microwire. o Plot of forward and backward PL intensity modulations at 610 nm versus θ, and exponential fit. p Dual-outcoupled intensity in the absence and presence of an electric field. Scale bar: 10 μm. q Output PL spectra of O1 and O2 under different field strengths ranging from 0 to 1.0 × 10⁶ V/m. a-h Reprinted with permission from ref. [28] Copyright 2018, Nature Publishing Group. i-q Reprinted with permission from ref. [35] Copyright 2018, American Association for the Advancement of Science