The discovery of superconductivity enabled the transport of electric charge without dissi-pation. Sustained, constructive work to develop sophisticated superconducting materials has led to enormous advances in the performance of superconductors and in raising their critical temperature. Interestingly, dissipation-free charge flow also exists in non-superconducting systems. Atoms, molecules, atomic clusters, and mesoscopic conduc-ting rings may carry such currents. Quantum-Hall systems also transport current loss-free if biased in a quantum-Hall plateau. Loss-free currents have furthermore been found to flow along the edges of topological insulators. In all systems described, dissipation-free transport is based on sustained quantum coherence and the suppression of inelastic scattering. Here, we report on our search for further possibilities to realize loss-free charge flow in non-superconducting devices or wires. We introduce quantum devices that use collapses of the wave functions and a subsequent coherent evolution of quantum states as essen-tial device elements. These devices are candidates to realize astonishing functional pro-perties, including lossless current transport in wires at high temperatures.
Host: Riccardo Comin