Ni–NiO–Ni tunnel junctions for terahertz and infrared detection
| Autor: | R. B. Laibowitz, Philip C. D. Hobbs, Frank R. Libsch |
|---|---|
| Rok vydání: | 2005 |
| Předmět: |
Materials science
Terahertz radiation business.industry Infrared Phonon Materials Science (miscellaneous) Dielectric Industrial and Manufacturing Engineering law.invention Optics law Tunnel junction Business and International Management Scanning tunneling microscope Spectroscopy business Quantum tunnelling |
| Zdroj: | Applied Optics. 44:6813 |
| ISSN: | 1539-4522 0003-6935 |
| Popis: | We present complete experimental determinations of the tunnel barrier parameters (two barrier heights, junction area, dielectric constant, and extrinsic series resistance) as a function of temperature for submicrometer Ni-NiO-Ni thin-film tunnel junctions, showing that when the temperature-invariant parameters are forced to be consistent, good-quality fits are obtained between I-V curves and the Simmons equation for this very-low-barrier system (measured phi approximately 0.20 eV). A splitting of approximately 10 meV in the barrier heights due to the different processing histories of the upper and lower electrodes is clearly shown, with the upper interface having a lower barrier, consistent with the increased effect of the image potential at a sharper material interface. It is believed that this is the first barrier height measurement with sufficient resolution for this effect to be seen. A fabrication technique that produces high yields and consistent junction behavior is presented as well as the preliminary results of inelastic tunneling spectroscopy at 4 K that show a prominent peak at -59 meV, shifted slightly with respect to the expected transverse optic phonon excitation in bulk NiO but consistent with other surface-sensitive experiments. We discuss the implications of these results for the design of efficient detectors for terahertz and IR radiation. |
| Databáze: | OpenAIRE |
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