Ultrafast switching and high-endurance nonvolatile memory enabled by intrinsic switchable polarization in semiconducting Janus monolayers

The discovery of two-dimensional (2D) semiconducting ferroelectric (SFe) materials marks a pivotal step toward the realization of ferroelectric random-access memory. Despite their potential as ideal platforms for ultrafast switching and ultralow power consumption, SFe monolayers remain largely unexplored. In this work, we demonstrate field-effect transistor employing monolayer Janus MoSeS, which exhibits switchable polarization when integrated on an amorphous ZrO2 layer with a high dielectric constant. The non-centrosymmetric structure of MoSeS enables gate-switchable spontaneous out-of-plane polarization, attributed to atomic displacements. The device demonstrates counterclockwise (CCW) memory windows of ~5 V, an on/off ratio exceeding 106 at zero gate bias, and a retention time much longer than 10,000 s. Furthermore, it achieves fatigue-free endurance over 107 cycles and ultrafast responses to 16.5 ns voltage spikes, resulting in ultralow power consumption of 113.9 fJ for programming and 89.8 fJ for erasing in each cycle. These performances establish Janus monolayers as promising candidates for next-generation nonvolatile memory and neuromorphic computing applications. Further work will be necessary to establish the switching mechanisms of the devices. The authors report the realization of switchable polarization field-effect transistors based on monolayer Janus MoSeS, showing on/off ratios exceeding 106 at zero gate bias, retention times up to 10,000 seconds, endurance of over 107 cycles, programming response times down to 16.5 ns and power consumption down to 113.9/89.8 fJ per program/erase cycle.