This project aims to realize and control multiferroic orders in true two-dimensional (2D) crystals. When reduced to a single layer, 2D crystals give rise to emergent phenomena that is absent in their three-dimensional (3D) counterparts—including massless Dirac fermions in graphene, valley Hall effect in monolayer transition metal dichalcogenides MoS2, among others. Recent predictions suggest highly-desired multiferroic states may also exist in 2D crystals. At the same time, their thin-layer-form facilitates access to electric, mechanical, and optical controls over their quantum states. The realization of 2D multiferroics would open the possibility for next-generation computational devices, sensors, and memory storage. In this project, we will create monolayer multiferroic crystals, investigate their structural, mechanical, electronic and optical properties, and ultimately control their phase transitions via mechanical, electric, and optical engineering.