Insulator interface effects in sputter‐deposited NbN/MgO/NbN (superconductor–insulator–superconductor) tunnel junctions

Insulator interface effects in sputter . . deposited NbN / MgO / NbN ( superconductor - insulator - superconductor } tunnel junctions

All refractory, NbN/MgO/NbN (superconductor-insulator-superconductor) tunnel junctions have been fabricated by in situ sputter deposition. The influence ofMgO thickness (0.8-6.0 nm) deposited under different sputtering ambients at various deposition rates on current-voltage (IV) characteristics of small-area ( 30 X 30 pm) tunnel junctions is studied. The NbN/MgO/NbN trilayer is deposited in sit...

Theory of Graphene-Insulator-Graphene Tunnel Junctions

Graphene-insulator-graphene vertical tunneling structures are discussed from a theoretical perspective. Momentum conservation in such devices leads to highly nonlinear current-voltage characteristics, which with gates on the tunnel junction form potentially useful transistor structures. Two prior theoretical treatments of such devices are discussed; the treatments are shown to be formally equiv...

Thermo-Coulomb effects in mesoseopic tunnel junctions

We present a study of the thermoelectric effects in tunnel junctions. In particular we calculate the thermopower coefficient S and the Peltier coefficient H. For macroscopic junctions we demonstrate the sensitivity of S and H to the structure of the density of states. For mesoscopic junctions we show that Coulomb effects modify the ordinary Onsager picture and the relation H = TS. The coefficie...

Interface states in CoFe2O4 spin-filter tunnel junctions

Spin polarization and barrier-oxidation effects at the Co alumina interface in magnetic tunnel junctions