András Deák

Fluctuating local moments, itinerant electrons, and the magnetocaloric effect: Compositional hypersensitivity of FeRh

We describe an ab initio disordered local moment theory for materials with quenched static compositional disorder traversing first-order magnetic phase transitions. It accounts quantitatively for metamagnetic changes and the magnetocaloric effect. For perfect stoichiometric B2-ordered FeRh, we calculate the transition temperature of the ferromagnetic-antiferromagnetic transition to be Tt= 495 K and a maximum isothermal entropy change in 2 T of |ΔS|=21.1 J K−1 kg−1. A large (40%) component of |ΔS| is electronic. The transition results from a fine balance of competing electronic effects which is disturbed by small compositional changes; e.g., swapping just 2% Fe of “defects” onto the Rh sublattice makes Tt drop by 290 K. This hypersensitivity explains the narrow compositional range of the transition and impurity doping effects.

Formation and stability of metastable skyrmionic spin structures with various topologies in an ultrathin film

We observe metastable localized spin configurations with topological charges ranging from

Thickness-dependent magnetic structure of ultrathin Fe/Ir(001) films: From spin-spiral states toward ferromagnetic order

Q=-3

Spin-correlations and magnetic structure in an Fe monolayer on 5d transition metal surfaces

to

Magnetism of Gadolinium: A First-Principles Perspective

Q=2

Role of temperature-dependent spin model parameters in ultra-fast magnetization dynamics

in a (Pt

Magnetic correlations beyond the Heisenberg model in an Fe monolayer on Rh(0 0 1)

_{0.95}

Skyrmions with attractive interactions in an ultrathin magnetic film

Ir

Relativistic spin-polarized KKR theory for superconducting heterostructures: Oscillating order parameter in the Au layer of Nb/Au/Fe trilayers

_{0.05}

Exchange interactions from a nonorthogonal basis: applications to 3d ferromagnets and graphene based systems.

)/Fe bilayer on Pd