Researchers from the Theory Department of the MPSD have realized the control of thermal and electrical currents in nanoscale devices by means of quantum local observations.
Measurement plays a fundamental role in quantum mechanics. At the same time, it also constitutes one of the main problems regarding the interpretation of this whole field. The best-known illustration of the principles of superposition and entanglement is Schrödinger’s cat. Not being visible from the outside, the cat resides in a coherent superposition of two states: it is alive and dead at the same time.
By means of a measurement, this superposition collapses to a concrete state: the cat is now either dead or alive. In this famous thought experiment a measurement of the “quantum cat” can be seen as an interaction with a macroscopic object collapsing the superposition onto a concrete state by destroying its coherence.
In their new article published in Nature PJ Quantum Materials, researchers from the MPSD (Max Planck Institute for the Structure and Dynamics of Matter) at CFEL (Center for Free-Electron Laser Science) in Hamburg together with collaborators from the University of the Basque Country (UPV/EHU) in San Sebastian and the Bremen Center for Computational Materials Science (BCCMS) discovered how a microscopic quantum observer is able to control thermal and electrical currents in nanoscale devices. Local quantum observation of a system can induce continuous and dynamic changes in its quantum coherence, which allows better control of particle and energy currents in nanoscale systems.
(Image©K. Aranburu )