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Updated: Jun 22, 2026
13:56
Probe Type II Band Alignment in One-Dimensional Van Der Waals Heterostructures Using First-Principles Calculations
Published on: October 12, 2019
Isotopic homojunction band engineering from diamond.
H Watanabe1, C E Nebel, S Shikata
1Diamond Research Center, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba Central 2-13, 1-1-1, Umezono, Tsukuba, Ibaraki 305-8568, Japan. hideyuki-watanabe@aist.go.jp
Science (New York, N.Y.)
|June 13, 2009
Summary
Researchers created diamond superlattices using carbon-12 and carbon-13 isotopes to confine electrons. This novel approach demonstrates effective carrier confinement in diamond, paving the way for new semiconductor applications.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Quantum Engineering
Background:
- Semiconductor charge carrier confinement is typically achieved using heterostructures with varying elemental compositions.
- Examples include aluminum gallium arsenide (AlGaAs) and gallium arsenide (GaAs) layers.
Purpose of the Study:
- To fabricate and characterize diamond superlattices using isotopically pure carbon isotopes.
- To demonstrate carrier confinement in diamond via engineered band-gap differences.
Main Methods:
- Fabrication of multilayer diamond structures using carbon-12 (12C) and carbon-13 (13C) isotopes.
- Utilizing a band-gap energy difference of 17 millielectron volts for confinement.
- Cathodoluminescence spectroscopy at 80 Kelvin to analyze excitonic recombination.
Main Results:
- Successful fabrication of diamond superlattices with both thin (30 nm) and thick (up to 350 nm) layers.
- Observation of excitonic recombination shifting from the higher-energy 13C band to the lower-energy 12C band.
- Demonstration of effective electron confinement within the diamond superlattice structure.
Conclusions:
- Diamond superlattices composed of different carbon isotopes can effectively confine charge carriers.
- This isotopic engineering approach offers a new method for creating quantum wells in diamond.
- The findings open possibilities for advanced diamond-based electronic and optoelectronic devices.
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