Hier finden Sie wissenschaftliche Publikationen aus den Fraunhofer-Instituten.

Isotopic homojunction band engineering from diamond

Band-Ingineering von Diamant mit Isotopen
: Watanabe, H.; Nebel, C.E.; Shikata, S.


Science 324 (2009), No.5933, pp.1425-1428
ISSN: 0036-8075
Journal Article
Fraunhofer IAF ()
Diamant; diamond; Isotope; Exziton; Übergitter; superlattice

Confinement of charge carriers in semiconductors by quantum wells is usually accomplished with layers that vary in elemental composition, such as aluminum gallium arsenide and gallium arsenide. We fabricated diamond superlattices by creating multilayer structures of isotopically pure carbon isotopes carbon-12 (exp 12C) and carbon-13 (exp 13C), which confine electrons by a difference in band-gap energy of 17 millielectron volts. Cathodoluminescence experiments performed at 80 kelvin showed that excitonic recombination in the higher-energy band of 13C vanishes in favor of increased recombination in the lower-energy 12C material. Carrier confinement was achieved in diamond superlattices made up of both thinner (30 nanometers) and thicker (up to 350 nanometers) layers.