Quasiparticle Injected YBa2Cu3O7-y Three Terminal Device

We report the first measurements on quasiparticle injected high Tc devices based on the tunnel injection of quasiparticles using an Au/MgO/YBa2Cu3O7-y (YBCO) trilayer grown on a SrTiO3(100) bi-crystal or a MgO(100) substrate. It is found that with the increase of injection current, Josephson current and the film critical current decrease and become zero at a relatively low injection current density. The current gain goes over 1, suggesting that this device is very promising.