An international team led by Prof. Nathan Goldman, Faculty of Science, Université libre de Bruxelles, predicts a novel form of quantization law, which involves a distinct type of physical observable: the heating rate of a quantum system upon external shaking.
In order to understand this concept, let us first consider a simpler analogous picture: When an ice cube is placed into a micro-wave oven, the latter excites the water molecules, hence leading to a progressive melting of the ice; during this heating process, the number of molecules that form the ice decreases in time, a process which can be quantified by a heating rate.
In the present article, the authors demonstrate how, under specific circumstances, such heating rates must satisfy an elegant and precise quantization law.
Specifically, the authors explain that this phenomenon takes place when a physical system, which initially forms an exotic state of matter, is heated up in a controlled manner; upon heating, particles are ejected from the topological phase and the corresponding heating rate is shown to satisfy the aforementioned quantization law.
A crucial aspect of this novel quantization law is that it is dictated by the topological nature of the initial phase of the system, in direct analogy with the quantization of the conductance in solids.
This elegant relation between the physical quantization of conductance and the abstract concept of topology opened the door to the exploration of a wide family of exotic states of matter, the so-called topological phases, whose discovery was recently honored by the 2016 Nobel Prize in Physics.
Besides the elegance of this novel quantization law for heating rates, this discovery has an important corollary: heating up a quantum system can be used as a universal probe for exotic states of matter.