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Large Bandgap Shrinkage from Doping and Dielectric Interface in Semiconducting Carbon Nanotubes.

ABSTRACT: The bandgap of a semiconductor is one of its most important electronic properties. It is often considered to be a fixed property of the semiconductor. As the dimensions of semiconductors reduce, however, many-body effects become dominant. Here, we show that doping and dielectric, two critical features of semiconductor device manufacturing, can dramatically shrink (renormalize) the bandgap. We demonstrate this in quasi-one-dimensional semiconducting carbon nanotubes. Specifically, we use a four-gated device, configured as a p-n diode, to investigate the fundamental electronic structure of individual, partially supported nanotubes of varying diameter. The four-gated construction allows us to combine both electrical and optical spectroscopic techniques to measure the bandgap over a wide doping range.

SUBMITTER: Comfort E

PROVIDER: S-EPMC4919786 | biostudies-literature | 2016 Jun

REPOSITORIES: biostudies-literature

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Large Bandgap Shrinkage from Doping and Dielectric Interface in Semiconducting Carbon Nanotubes.

Comfort Everett E Lee Ji Ung JU

Scientific reports 20160624

The bandgap of a semiconductor is one of its most important electronic properties. It is often considered to be a fixed property of the semiconductor. As the dimensions of semiconductors reduce, however, many-body effects become dominant. Here, we show that doping and dielectric, two critical features of semiconductor device manufacturing, can dramatically shrink (renormalize) the bandgap. We demonstrate this in quasi-one-dimensional semiconducting carbon nanotubes. Specifically, we use a four-g ...[more]

PMID: 27339272

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