No abstract

It is well known that metal/Tin-dioxide/metal sandwich structures exhibit a field-assisted lowering of the potential barrier between donor-like center and the conduction band edge, known as the Poole-Frenkel effect. This behavior is indicated by a linear dependence of Iog  on , where is the current density, and is the applied voltage. In this study, the electrical properties of Cu/nano-SnO2/Cu sandwich structures were investigated through current-voltage measurements at room temperature. Also, an attempt to explore the governing current flow mechanism was tried. Our results indicate that noticeable feature appearing clearly in the current-voltage characterization is the Poole-Frenkel and space-charge-limited conduction mechanisms.

No abstract

Exact boundary conditions for open quantum devices with constant potential asymptotics are presented and implemented into a numerical treatment of the one-dimensional time-dependent Schrödinger equation. A time-dependent analysis of the resonant tunneling double-barrier (RTDB) structure demonstrates their superiority over previous approaches. Our self-consistent study reveals microscopic details of the transient current in the system under an external time-dependent bias. Two time regimes characterize the charge transport in a RTDB in response to an applied bias. The ultrafast response of the system occurs in the contact regions within approximately 100 fs. This response time is of the order of the inverse bulk plasma frequency and is essentially independent of the applied bias. The second time regime is characterized by current oscillations which sensitively depend on the applied bias and structural parameters.

No abstract