News & Scientific Highlights

Strontium titanate is a wide band gap semiconductor. Its surface can be rendered conductive by a mild annealing in vacuum. The present study reveals that by deposition of less than a monolayer of non-volatile organic molecules such as tetracyanoquinodimethane (TCNQ) this conductivity can be completely turned off. In view of the small size of TCNQ (ca. 1 nm) this could allow new pathways toward oxide-based electronics.

3d transition metals often exhibit a quenched orbital moment when in a solid state system. Therefore, the proposition of a large unquenched orbital moment for V in VI₃ caused some surprise and discussion in the scientific community. Experimental and theoretical works diverge on the fact of whether the orbital moment is quenched or not. In our work we have been able to give an answer this open issue, proposing also a model for the ground state of VI₃.

Lithium fluoride is an important material which is technologically exploited in spintronics and organic light emitting devices. It turns out that there is a vast difference between the morphologies of ultrathin lithium fluoride grown on the (100) facet of a silver single crystal.  At room temperature dendrites are obtained while at elevated temperature lithium fluoride forms square islands. The system is an interesting model to study the crossover between diffusion limited aggregates and island growth.

A team of the Leibniz Institute for Solid State Research (IFW) from Dresden, Germany, led by Dr Alexey Popov has now demonstrated a record blocking temperature of 28 Kelvin at which the magnetic bistability still survives in a submonolayer of a chemically functionalized species of endofullerenes. In this research, X-ray magnetic circular dichroism measurements at low temperatures and high magnetic field at the X-Treme beam line are crucial. The results pave the way toward using such single-molecule magnets as information carriers or magnetic bits.

Within this synergetic collaboration, PSI scientists have investigated the correlation between magnetic and electronic ordering in NdNiO3 by tuning its properties through proximity to a ferromagnetic manganite layer. The main outcome is that the stray magnetic field from the manganite layer causes a novel ferromagnetic-metallic (FM-M) phase in NNO. This work demonstrates the utilization of heterostructure engineering for creating novel quantum phases.

The authors demonstrate the stability of ferromagnetic order of one unit cell thick optimally doped manganite (La0.7Ba0.3MnO3, LBMO) epitaxially grown between two layers of SrRuO3 (SRO). LBMO shows ferromagnetism even above SRO Tc. Density Functional Theory calculations help understand the reasons behind this interesting result.

A research team centered at the X-Treme beam line at the Swiss Light Source has demonstrated that spin-phonon coupling plays a major role in enhancing the magnetic stability of so-called lanthanide phthalocyanine double decker single-molecule magnets. This understanding is important in order to employ such molecules in future spintronics applications.