Electrically switchable liquid-crystal-core waveguides fabricated using a removable fibre template

A simple and low-cost fabrication method for electrically switchable liquid-crystal-core waveguides is demonstrated using a removable fibre template. A UV-curable optical adhesive (NOA65) is coated on an indium–tin–oxide (ITO) substrate, and a polymer fibre is placed on the surface to define the channel geometry. After UV curing, the fibre is removed, leaving a shallow circular-segment groove that serves as the liquid crystal (LC) core channel. When an external voltage is applied, the LC molecules reorient along the electric field, increasing the effective refractive index of the LC-core and enabling optical confinement within the channel. The guiding effect disappears once the voltage is removed. The measured switching behaviour shows a switch-on time below 200 ms and a relaxation time of approximately 6 s, consistent with the electro-optic response expected for an LC layer with an effective thickness of several tens of micrometres. This fibre-template approach provides a straightforward route for rapidly prototyping electrically controllable LC photonic channels without conventional lithographic fabrication processes.