Scientists and businesses are faced with new challenges as a result of the development of new information and communication technologies. The most promising method to address these issues is to design new quantum materials, whose remarkable features are derived from quantum physics.
Artistic view. Curvature of the space fabric due to the superposition of spin and orbital states at the interface between lanthanum aluminate (LaAlO3) and strontium titanate (SrTiO3). Image Credit: Xavier Ravinet–UNIGE
Researchers from the University of Salerno, the University of Utrecht, and the University of Delft have joined a global collaboration led by the University of Geneva (UNIGE) to develop a material that allows the curvature of the space in which electrons evolve to regulate their behavior.
These features are of interest for next-generation electronic devices, particularly future optoelectronics. These findings were published in the journal Nature Materials.
Future telecommunications will require the development of new, incredibly powerful electronic devices. They must be capable of processing electromagnetic signals at previously unheard-of rates in the picosecond range, which is one-thousandth of a billionth of a second.
This is unimaginable with current semiconductor materials, such as silicon, which is extensively used in electronic components such as phones, computers, and gaming consoles. To do this, scientists and industry are concentrating on the development of novel quantum materials.
These quantum materials could be used to capture, manipulate, and transmit information-carrying signals (for example, photons, in the case of quantum telecommunications) within new electronic devices due to their special properties, particularly the collective reactions of the electrons that constitute them.
They can also function in hitherto unexplored electromagnetic frequency regions, which would pave the path for extremely fast communication systems.
A Warp Drive
One of the most fascinating properties of quantum matter is that electrons can evolve in a curved space. The force fields, due to this distortion of the space inhabited by the electrons, generate dynamics totally absent in conventional materials. This is an outstanding application of the principle of quantum superposition.
Andrea Caviglia, Study Last Author and Full Professor, Department of Quantum Matter Physics, Faculty of Science, University of Geneva
The international team of researchers from the Universities of Geneva, Salerno, Utrecht, and Delft created a material in which the curvature of the space fabric is adjustable after conducting an initial theoretical investigation.
We have designed an interface hosting an extremely thin layer of free electrons. It is sandwiched between strontium titanate and lanthanum aluminate, which are two insulating oxides.
Carmine Ortix, Study Coordinator and Professor, University of Salerno
This combination enables the creation of specific electronic geometric configurations that are controlled on demand.
One Atom a Time
The study team employed an innovative technique for fabricating materials at the atomic scale to accomplish this. The atoms were piled one on top of the other using laser pulses.
The researchers stated, “This method allowed us to create special combinations of atoms in space that affect the behavior of the material.”
Although the possibility of technological application is still a long way off, this new material opens up new vistas in the investigation of extremely fast electromagnetic signal manipulation.
The development of new sensors can also be aided by these findings. To more clearly ascertain this material’s potential applications, the study team's next step will be to continue to monitor how it responds to high electromagnetic frequencies.
Journal Reference
Lesne, E., et al. (2023) Designing spin and orbital sources of Berry curvature at oxide interfaces. Nature Materials. doi:10.1038/s41563-023-01498-0.