Basel – In the computers of the future, information will be stored in the form of quantum bits. These have typically been created in the form of individual electrons, leading to various problems. Basel researchers have now solved this by removing electrons.
To create quantum bits, or qubits for short, an electron is placed within an enclosed area of a semiconductor. The spin causes the electron to behave like a small permanent magnet. As the University of Basel explains in a statement, researchers can apply an external magnetic field to influence the spin and cause it to rotate. The direction of this rotation can then be used to encode information.
The problem until now is that nuclear spins of the surrounding atoms also generate magnetic fields, distorting the external magnetic field and interfering with the way the qubits are programmed and read. Researchers at the University of Basel led by Professor Richard Warburton from the Department of Physics have now solved this problem by removing a specific electron to create a positively charged hole in the collection of electrons.
As a hole also has a spin, the researchers have been able to manipulate it to encode information. And because a hole is positively charged, it is effectively “immune” to the positively charged nuclei of the surrounding atoms.
The Basel researchers, who collaborated with researchers from Ruhr University Bochum and the University of Lyon, reported their findings in the journal Nature Materials. The project received funding from the National Center of Competence in Research Quantum Science and Technology, the Swiss National Science Foundation and the EU.