Ferroelectric Optical Memristors Enabled by Non-Volatile Electro-Optic Effect.

Memristors enable non-volatile memory and neuromorphic computing. Optical memristors are the fundamental element for programmable photonic integrated circuits due to their high-bandwidth computing, low crosstalk, and minimal power consumption. Here, an optical memristor enabled by a non-volatile electro-optic (EO) effect, where refractive index modulation under zero field is realized by deliberate control of domain alignment in the ferroelectric material Pb(MgNb)O-PbTiO(PMN-PT) is proposed. The non-volatile EO memristor is designed exclusively for the modulation of the optical phase without degrading the optical transparency, and it allows the support for deterministic and repeated non-volatile multilevel EO states. A non-volatile tunable waveplate composed of the optical memrisor for free-space optics, which allows for deterministic multilevel, and non-volatile phase shifts from 0 to π/2 is presented. The state switching rate of the memristor is less than 100 ms, with a switching energy consumption of 234 nJ, and the states can be retained for up to 12 h without requiring static power consumption. These results demonstrate a novel approach to fully realizing non-volatile optical memristors, where only optical phase modulation is involved, providing unprecedented opportunities for the development of new ferroelectric memristors.