Quantum dynamics in single-molecule magnets

Dr. W. Wernsdorfer, Louis Nel Laboratory - CNRS, Grenoble.

The interface between classical and quantum physics has always been an interesting area, but its importance has nevertheless grown with the current explosive thrusts in nanoscience. Taking devices to the limit of miniaturization (the mesoscale and beyond) where quantum effects become important makes it essential to understand the interplay between the classical properties of the macroscale and the quantum properties of the microscale. This is particularly true in nanomagnetism, where many potential applications require monodisperse, magnetic nanoparticles. One source of such species are single-molecule magnets (SMMs), individual molecules that function as single-domain magnetic particles. Below their blocking temperature (TB), they exhibit magnetization hysteresis, the classical macroscale property of a magnet, as well as quantum tunnelling of magnetization (QTM) and quantum phase interference, the properties of a microscale entity. QTM is advantageous for some potential applications of SMMs, e.g. in providing the quantum superposition of states for quantum computing, but is a disadvantage in others such as information storage. I will review recent advances in this field of research.