Magnetic Remanence in Single Atoms

Wednesday, 24 February 2016, at 11:15 in Y36 J33

The prime feature of a magnet is to retain a substantial fraction of its saturation magnetization in the absence of an external magnetic field. Realizing magnetic remanence in a single atom allows for storing and processing information in the smallest unit of matter. I will show that individual Ho atoms adsorbed on ultrathin MgO(100) films on Ag(100) exhibit magnetic remanence up to a temperature of 30 K and a relaxation time of 1500 s at 10 K. This extraordinary stability is achieved by realizing a symmetry-protected magnetic ground state and by decoupling the Ho spin from the Ag electrons and soft phonons with a MgO buffer layer.