Long Range Intrinsic Magnetic Order in Bulk Semiconducting MoTe₂ and MoSe₂

The search for semiconducting materials with intrinsic dilute magnetism has been an ongoing challenge for many years. The semiconducting transition metal dichalcogenides have drawn great interest due to a wide array of electrical and optical applications. In this work, we report the direct observation of long-range magnetic order below T_M=40K and T_M=100K in bulk 2H-MoTe2 and 2H-MoSe2 respectively by muon spin relaxation/rotation (µSR). To investigate the origin of the long-range magnetic order, we perform scanning tunneling microscopy (STM) which reveals a uniform density of intrinsic defects in the materials. Atomic-resolution STM reveals that the primary defects are substitutions of chalcogen atoms, likely by molybdenum. Hubbard density functional theory (DFT) simulations predict that these molybdenum substitutional defects induce magnetic moments at defect sites with long range interaction. Scanning tunneling spectroscopy taken at defect sites is also in confirmation with the L-DOS calculated via the DFT simulations . Thus, we conclude that the long range magnetic order observed via µSR is native to the materials, due to interacting intrinsic magnetic defects.