Sub‐1‐Volt Electrically Programmable Optical Modulator Based on Active Tamm Plasmon

Abstract Reconfigurable optical devices hold great promise for advancing high‐density optical interconnects, photonic switching, and memory applications. While many optical modulators based on active materials have been demonstrated, it is challenging to achieve a high modulation depth with a low operation voltage in the near‐infrared (NIR) range, which is a highly sought‐after wavelength window for free‐space communication and imaging applications. Here, electrically switchable Tamm plasmon coupled with poly(3,4‐ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) is introduced. The device allows for a high modulation depth across the entire NIR range by fully absorbing incident light even under epsilon near zero conditions. Optical modulation exceeding 88% is achieved using a CMOS‐compatible voltage of ±1 V. This modulation is facilitated by precise electrical control of the charge carrier density through an electrochemical doping/dedoping process. Additionally, the potential applications of the device are extended for a non‐volatile multi‐memory state optical device, capable of rewritable optical memory storage and exhibiting long‐term potentiation/depression properties with neuromorphic behavior.