Looking Inside the Perchlorinated Trityl Radical/Metal Spinterface through Spectroscopy

Persistent and stable organic molecules with an open-shell electronic configuration have long been known and extensively studied mainly in solution. Only recent is instead the study of organic radicals as laterally self-assembled monolayers immobilized on substrates towards their application in devices, e.g. in organic spintronics [1].

Nanopatterning reconfigurable magnetic landscapes via thermally assisted scanning probe lithography

The search for novel tools to control magnetism at the nanoscale is crucial for the development of new paradigms in optics, electronics and spintronics. To date, the fabrication of magnetic nanostructures has been achieved mainly through irreversible structural or chemical modifications.

Here, we propose a new approach, based  on thermally assisted magnetic scanning probe lithography (tam-SPL),  for creating reconfigurable  magnetic nanopatterns by crafting, at the nanoscale, the magnetic anisotropy landscape of a ferromagnetic layer exchange-coupled to an antiferromagnetic layer. By performing localized field cooling with the hot tip of a scanning probe microscope, magnetic structures, with arbitrarily oriented magnetization and tunable unidirectional anisotropy, are reversibly patterned without modifying the film chemistry and topography. This opens unforeseen possibilities for the development of novel metamaterials with finely tuned magnetic properties, such as magnonic crystals allowing active manipulation of spin waves. In this context, we present a proof-of-concept experiment, performed by micro-focused Brillouin light scattering (µ-BLS), showing that local control of the spin wave excitation and propagation can be obtained in reconfigurable magnetic tracks patterned with tam-SPL.

A Roadmap for Controlled and Efficient n-type Doping of Self-assisted GaAs Nanowires Grown by Molecular Beam Epitaxy

N-type doping of GaAs nanowires has proven to be difficult because the amphoteric character of silicon impurities, routinely used for the n-type doping of GaAs epilayers,  is enhanced by the nanowire growth mechanism and growth conditions. Among the various possible donor impurities for GaAs NWs, tellurium represents a good candidate since it is a very effective dopant in GaAs epilayers and does not present any risk of amphoteric behavior.

Electric control of magnetism at the Fe/BaTiO3 interface

Using electric fields for magnetic writing is a very appealing opportunity, however, bulk multiferroic materials at room temperature have not been yet found. Instead, interfacial magnetoelectric coupling could be a viable path to achieve electrical writing of magnetic information in spintronic devices.

Here, we report on a room temperature ON-OFF electrical switching of the interfacial magnetization at the Fe/BaTiO3 interface.