Is there anybody out there?
By Ian Sample A SUPERCONDUCTING transistor should help astronomers pick up signals from far-off solar systems that are too faint to be detected. “The problem with detecting photons from far out is that their energies are very low,” says Giampiero Pepe of the University of Naples. To solve the problem, Pepe teamed up with Norman Booth at the University of Oxford to make a device called a quasiparticle-trapping transistor, or “quatratran”, which works at a temperature of 4 kelvin. Incoming photons strike a layer of niobium. Because niobium is superconducting at this temperature,