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Localized electron states near a metal/semiconductor nanocontact
Denis O Demchenko1, Lin-Wang Wang
1Computational Research Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA. dodemchenko@lbl.gov
Nano Letters
|September 25, 2007
Summary
Metallic electrodes create localized electron/hole states in nanowires, significantly altering their electronic structure. This effect, dependent on nanowire size, can change the band gap, impacting device performance.
Area of Science:
- Physics
- Materials Science
- Nanotechnology
Background:
- Understanding the electronic properties of nanowires is crucial for nanoscale electronic devices.
- The interaction between nanowires and metallic electrodes can significantly influence their behavior.
Purpose of the Study:
- To investigate the electronic structure of nanowires in contact with metallic electrodes.
- To quantify the impact of electrode proximity on nanowire electronic states and band gap.
Main Methods:
- Incorporation of electrostatic image potential into the atomistic single-particle Schrödinger equation.
- Calculation of electronic structure for various electrode/nanowire geometries.
- Analysis of nanowire size dependence on localization effects.
Main Results:
- Localized electron/hole states are formed near the metallic electrode.
- A strong dependence of this localization on nanowire size was observed.
- Band gap changes of up to 0.5 eV were demonstrated in 3 nm diameter CdSe nanowires.
Conclusions:
- Metallic electrodes induce significant changes in nanowire electronic structure.
- Nanowire size is a critical factor determining the extent of electronic state localization.
- The findings provide insights into designing nanowire-based electronic devices.
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