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Stephanos, C.

Publications and source records attributed to Stephanos, C..

Transparency of graphene for low-energy electrons measured in a vacuum-triode setup

Graphene, being an atomically thin conducting sheet, is a candidate material for gate electrodes in vacuum electronic devices, as it may be traversed by low-energy electrons. The transparency of graphene to electrons with energies between 2 and 40 eV has been measured by using an optimized vacuum-triode setup. The measured graphene transparency equals ∼60% in most of this energy range. Based on these results, nano-patterned sheets of graphene or of related two-dimensional materials are proposed as gate electrodes for ambipolar vacuum devices.

36 MATERIALS SCIENCE↗

Interface-induced $d$-wave pairing

We discuss a scenario for interface-induced superconductivity involving pairing by dipolar excitations proximate to a two-dimensional electron system controlled by a transverse electric field. If the interface consists of transition-metal oxide materials, the repulsive on-site Coulomb interaction is typically strong and a superconducting state is formed via exchange of nonlocal dipolar excitations in the d-wave channel. Perspectives to enhance the superconducting transition temperature are discussed.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗