Scientists unlock new way to control quantum supercurrents using dissipation
Researchers have discovered that specially designed quantum junctions can create unusual physical states—called exceptional points—that let dissipation actually enhance electrical flow. This finding could enable more precise control of superconducting devices for quantum computing and energy applications, opening a path to devices that harness loss rather than fight it.
Originaltitel: Non-Hermitian multiterminal phase-biased Josephson junctions
<p>We study non-Hermitian Josephson junctions formed by multiple superconductors and discover the emergence of exceptional points entirely determined by the interplay of the distinct superconducting phases and nonHermiticity due to normal reservoirs. In particular, in Josephson junctions with three and four superconductors, we find stable lines and surfaces of exceptional points protected by non-Hermitian topology and highly tuneable by the superconducting phases. We also discover that, in Josephson junctions formed by laterally coupled superconductors, exceptional points can result from hybridized Andreev bound states and lead to the enhancement of supercurrents controlled by dissipation. Our work unveils the potential of multiterminal Josephson junctions for realizing higher-dimensional topological non-Hermitian superconducting phenomena.</p>