Tuning the density of zero-field skyrmions and imaging the spin configuration in a two-dimensional Fe3GeTe2 magnet

Abstract With the advent of ferromagnetism, two-dimensional (2D) van der Waals (vdW) magnets have attracted particular attention in exploring topological spin textures, such as skyrmions used for next-generation spintronic devices. The discovery magnetic Fe 3 GeTe 2 (FGT) has sparked interest investigating configurations FGT. Here, we an situ Lorentz microscope to directly demonstrate generation and sustainability Bloch-type a zero field over wide temperature range 2D vdW By tuning value external field, highest-density hexagonal skyrmion lattice emerges after reducing zero. Moreover, by tilting FGT nanosheet, found that field-free can also represent invisible contrast when tilt angle is zero, but reversed at high angle. On basis our experiments, discuss possible mechanisms variable contrast. These findings offer valuable insights into shed light on identification via microscopy.