Energy landscape study by telegraph noise of domain wall motion

The energy barrier landscape in-between two adjacent pinning sites of magnetic domain wall was investigated by telegraph noise of domain wall motion. The telegraph noise provided numerous depinning times for each pinning site, from which the depinning energy barrier characteristics were extracted. By generating the telegraph noise under application of magnetic field and electric current, the energy barrier landscape could be reconstructed with the barrier height and lateral size of the adjacent pinning sites. The lateral size fits well with other independent estimation based on the signal level with the focused laser beam, providing the validity of the present approach.