Electron transport through Al–ZnO–Al: An ab initio calculation

Abstract

The electron transport properties of ZnO nano-wires coupled by two aluminium electrodes were studied by ab initio method based on non-equilibrium Green's function approach and density functional theory. A clearly rectifying currentvoltage characteristics was observed. It was found that the contact interfaces between Al-O and Al-Zn play important roles in the charge transport at low bias voltage and give very asymmetric I-V characteristics. When the bias voltage increases, the negative differential resistance occurs at negative bias voltage. The charge accumulation was calculated and its behavior was found to be well correlated with the I-V characteristics. We have also calculated the electrochemical capacitance which exhibits three plateaus at different bias voltages which may have potential device application.

First principles study on the spin dependent electronic behavior of Co doped ZnO structures joining the Al electrodes

“…For a ZnO structure joining the Al electrodes, the electrode-ZnO coupling was already found to play a crucial role in the electron transport at low bias in Ref. [31] where spin property was not involved. Thus, in our case, G "# is determined by both PDOS at the Fermi level and coupling of orbitals of ZnO based structures to the Al electrodes.…”

“…In Ref. [30,31] electrodes used were Au and Al, respectively. A ZnO based system between metal electrodes (Al or Au) can result in Schottky-like contact at the interface, which we confirmed in the present study.…”

“…In many device structures electrodes are taken as metal surfaces, like Ni, Au, Al, etc. Theoretically, a pure ZnO structure between the metal electrodes were investigated [30,31]. In Ref.…”

Performance of a 260 Hz pulse tube cooler with metal fiber as the regenerator material

“…In 1996, Godshalk made the first attempt of such a system and obtained a noload temperature of 147 K at 350 Hz, which was driven by a thermoacoustic engine [1]. In recent years, considerable progress has been made on 300 Hz pulse tube coolers driven by a standing-wave thermoacoustic compressor in our lab [2][3][4]. In 2009, through a series of improvements, the system reached a no-load temperature of 63 K and 1.04 W cooling power at 80 K with 500 W input power [4].…”

“…In recent years, considerable progress has been made on 300 Hz pulse tube coolers driven by a standing-wave thermoacoustic compressor in our lab [2][3][4]. In 2009, through a series of improvements, the system reached a no-load temperature of 63 K and 1.04 W cooling power at 80 K with 500 W input power [4]. Under the same piston displacement the increase of frequency can effectively increase the compressor output acoustic power, resulting in a smaller system volume and mass.…”