New material provides a key to explaining superconductivity

At Helmholtz, more than 8,000 doctoral candidates conduct research. Eleven of them have now been honored for their original and outstanding work, among them Dr Israel Ibukun Olaniyan from the HZB. His doctoral thesis "Ferroelectricity at the nanoscale in epitaxial BaTiO₃ on silicon" in the group of Professor Catherine Dubourdieu represents a step towards a new nanoelectronics based on topological defects, that can potentially help to create an energy efficient information technology.

The team at the IRIS beamline at BESSY II has created a new experimental option: They achieved infrared nanoscopy with a spatial resolution of around 50 nm at very long THz wavelengths. This was possible thanks to a temporal pattern of light pulses known as the low-alpha operating mode at BESSY II. Worldwide, BESSY II is the only synchrotron light source at which users could perform nanoscopy in a single setup from 25 to 4000 cm^-1, a unique opportunity for ultra-broadband characterisation of complex materials at the nanoscale in both the life sciences and materials sciences.

A team at HZB has, for the first time, reported polar vortices in (BaTiO₃/SrTiO₃)₁₀ superlattices on silicon. These results expand the range of materials and substrates on which polar topological textures can occur and open up new options for incorporating complex ferroelectric states into silicon-based technologies.