HZB Newsroom

Synchrotron radiation sources generate highly brilliant light pulses, ranging from infrared to hard X-rays, which can be used to gain deep insights into complex materials. An international team has now published an overview on synchrotron methods for the further development of quantum materials and technologies in the journal Advanced Functional Materials: Using concrete examples, they show how these unique tools can help to unlock the potential of quantum technologies such as quantum computing, overcome production barriers and pave the way for future breakthroughs.

Dr Hebatalla Elnaggar is setting up a new Helmholtz Investigator Group at HZB. At BESSY II, the materials scientist will investigate so-called magnons in magnetic perovskite thin films. The aim is to lay the foundations for future terahertz magnon technology: magnonic devices operating in the terahertz range could process data using a fraction of the energy required by the most advanced semiconductor devices, and at speeds up to a thousand times faster.

For the first time, a team at BESSY II has succeeded in demonstrating the one-dimensional electronic properties in phosphorus. The samples consisted of short chains of phosphorus atoms that self-organise at specific angles on a silver substrate. Through sophisticated analysis, the team was able to disentangle the contributions of these differently aligned chains. This revealed that the electronic properties of each chain are indeed one-dimensional. Calculations predict an exciting phase transition to be expected as soon as these chains are more closely packed. While material consisting of individual chains with longer distances is semiconducting, a very dense chain structure would be metallic.

An international team has succeeded at BESSY II for the first time to elucidate how ultrafast spin-polarised current pulses can be characterised by measuring the ultrafast demagnetisation in a magnetic layer system within the first hundreds of femtoseconds. The findings are useful for the development of spintronic devices that enable faster and more energy-efficient information processing and storage. The collaboration involved teams from the University of Strasbourg, HZB, Uppsala University and several other universities.

Diamonds with certain optically active defects can be used as highly sensitive sensors or qubits for quantum computers, where the quantum information is stored in the electron spin state of these colour centres. However, the spin states have to be read out optically, which is often experimentally complex. Now, a team at HZB has developed an elegant method using a photo voltage to detect the individual and local spin states of these defects. This could lead to a much more compact design of quantum sensors.

Silicon is the best-known semiconductor material. However, controlled nanostructuring drastically alters the material's properties. Using a specially developed etching apparatus, a team at HZB has now produced mesoporous silicon layers with countless tiny pores and investigated their electrical and thermal conductivity. For the first time, the researchers elucidated the electronic transport mechanism in this mesoporous silicon. The material has great potential for applications and could also be used to thermally insulate qubits for quantum computers.

Nanostructures with specific electromagnetic patterns promise applications in nanoelectronics and future information technologies. However, it is very challenging to control those patterns. Now, a team at HZB examined a specific class of nanoislands on silicon with interesting chiral, swirling polar textures, which can be stabilised and even reversibly switched by an external electric field.