  Two-dimensional materials hosting ferroelectricity and ferromagnetism are
crucial for low-power and high-speed information processing technologies.
However, intrinsic 2D multiferroics in the monolayer limit are rare. Here, we
demonstrate that monolayer CrTe, obtained by cleaving the [002] surface, is
dynamically stable multiferroic at temperatures beyond room temperature. We
show that it orders ferromagnetically with significant in-plane
magnetocrystalline anisotropy, and it is a half-metal featuring a large
half-metal gap. Remarkably, the broken inversion symmetry and buckled geometry
of monolayer CrTe make it a ferroelectric with a large spontaneous out-of-plane
polarization and significant magnetoelectric coupling. In addition, we
demonstrate polarization or electric field-induced tunability of the anomalous
Hall effect, accompanied by substantial bandstructure modulation. Our findings
establish monolayer CrTe as a room-temperature multiferroic with great
potential for applications in spintronics and ferroelectric devices.
