Impact of organic capping layer on the magnetic anisotropy of ultrathin Co films

Abstract

Using combined magnetometry and ferromagnetic resonance studies, it is shown that introduction of a hydrocarbon cover layer leads to an increase of the contribution of the surface anisotropy to the effective magnetic anisotropy energy of hexagonal close-packed 0001 cobalt films, largely enhancing the perpendicular anisotropy. Due to a weak electronic interaction of the organic molecules with the Co atoms, an increase of surface anisotropy could be explained by the presence of an electric field at the organic-material/Co interface and by modification of surface atoms charge configuration.

In situ compensation method for high-precision and high-sensitivity integral magnetometry

“…Since the advent of commercially available, affordable, automated (computer controlled), basic fault-tolerant and user-friendly superconducting quantum interference device (SQUID) integral magnetometers in the early 90s, sensitive SQUID-based magnetometry has now established itself as an indispensable everyday characterization and experimental tool in modern science. It has become routinely performed on a wide range of different types of samples such as ultrathin films [1,2,3,4,5,6], nanoparticles [7,8,9,10,11], nanowires [12,13], nanocomposites [14], quantum dots [15], graphene [16,17], dilute magnetic [18,19,20,21,22], and ferromagnetic semiconductor epilayers [23,24]. It currently enters the realms of organic spintronics [25], biology [26], and arXiv:1809.02346v3 [cond-mat.mtrl-sci] 5 Jul 2019 topological matter [27,28].…”

Structural characterization and electronic properties of Ni/rubrene bilayers with alternative stacking sequences

“…A high surface anisotropy energy of 1.08 Â 10 À3 J m À2 was reported for a Co/hydrocarbon system. 24 The adsorbed carbon monoxide (CO) on ultrathin face-centred cubic (fcc) Fe films changed the direction of magnetization from in-plane (IP) to out-of-plane (OP). 25 Rubrene is one of the OSCs that shows numerous intriguing electrical properties, including a high mobility, long-excitation lifetime, and spin-relaxation length.…”

“…A high surface anisotropy energy of 1.08 × 10 −3 J m −2 was reported for a Co/hydrocarbon system. 24 The adsorbed carbon monoxide (CO) on ultrathin face-centred cubic (fcc) Fe films changed the direction of magnetization from in-plane (IP) to out-of-plane (OP). 25…”