Science Advances Journal: "Probing quantum coherence in single-atom electron spin resonance"

A team of scientist from the IBM Research Lab at Almaden (San Jose, USA), the IBS-QNS -Institute for Basic Science, Center for Quantum Nanoscience (Seoul, Korea) and the INL – International Iberian Nanotechnology Laboratory (Braga, Portugal), has been able to carry out a magnetic resonance experiment that probes an individual magnetic atom. This experiment permits them to examine, at the atomic scale, “quantum coherence”, an essential resource in the so-called quantum technologies.

Magnetic resonance is a technique that permits to obtain information about biological tissues from the measurement of the magnetic behaviour of atomic nuclei. In a conventional magnetic resonance measurement, such as those carried out at hospitals, it is necessary to integrate the signal coming from, at least, a trillion (1012) atoms.

“Being able to probe an individual magnetic atom, is very exciting”, says Joaquín Fernández-Rossier (INL), a theoretical physicist involved in the work. “This finding provides a deeper understanding of one of the main challenges that we are facing to build quantum computers, namely, to extend the lifetime of quantum coherence”.

These findings were reported in the prestigious Journal Science Advances, edited by the American Association for the Advancement of Science on February 16, 2018.

According to Joaquín Fernandez-Rossier, “understanding the decay of coherence at the atomic scale is essential to think of atomic-scale quantum devices”. “It is the ultimate limit regarding magnetic sensing, there is nothing smaller, except nuclei of course”, said the scientist who leads the Theory of Quantum Nanostructures research group at INL.

Click below and read the full article.