The Raw Material of Quantum Radar Arrives at Room Temperature

MIT researchers report in Nature Electronics a cavity-magnonic device that generates paired correlated microwave signals at room temperature: a yttrium iron garnet film on a printed circuit board splits one pump photon into two outputs at distinct frequencies with a strongly correlated phase relationship. A close look at why the dilution refrigerator has kept quantum illumination radar and correlation-assisted links confined to laboratories, what a warm pair source changes for whom, and the honest distance between strong correlations on a bench and the entangled, target-ranging quantum radar a program office could rely on.