Probing the atomic-scale ferromagnetism in van der Waals magnet CrSiTe3

As an emerging class of two-dimensional (2D) materials, van der Waals (vdW) magnets have attracted a lot of research attention since they can give access to fundamental physics and potential spintronic device applications. Among these 2D vdW magnets, CrSiTe3, as an intrinsic ferromagnetic semiconductor, exhibits great potentials in low-dimensional spintronics. Of particular interest in this 2D vdW magnet is the electronic and magnetic properties at the atomic-scale, which has yet been fully explored so far. Here, combing angle-resolved photoemission spectroscopy, bulk magnetic measurements, and synchrotron-based x-ray techniques, an unambiguous picture of the electronic and magnetic states of CrSiTe3 is presented. Hybridization of Cr-3d and Te-5p orbitals and the semiconducting behavior are confirmed by the band structure detection. Intrinsic ferromagnetism with a magnetic anisotropy constant of 1.56 x 10(5) erg/cm(3) is attributed to the superexchange interaction of the Cr3+ ions. In addition, temperature-dependent spin and orbital moments are determined, and a fitted critical exponent of 0.169 implies that CrSiTe3 is in good agreement with the 2D Ising model. More remarkably, unquenched orbital moments are experimentally evidenced, bringing CrSiTe3 with orbital-dependent intriguing effects and great potentials toward the spintronic devices.