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Dimensional crossover in semiconductor nanostructures.

ABSTRACT: Recent advances in semiconductor nanostructure syntheses provide unprecedented control over electronic quantum confinement and have led to extensive investigations of their size- and shape-dependent optical/electrical properties. Notably, spectroscopic measurements show that optical bandgaps of one-dimensional CdSe nanowires are substantially (approximately 100?meV) lower than their zero-dimensional counterparts for equivalent diameters spanning 5-10?nm. But what, exactly, dictates the dimensional crossover of a semiconductor's electronic structure? Here we probe the one-dimensional to zero-dimensional transition of CdSe using single nanowire/nanorod absorption spectroscopy. We find that carrier electrostatic interactions play a fundamental role in establishing dimensional crossover. Moreover, the critical length at which this transition occurs is governed by the aspect ratio-dependent interplay between carrier confinement and dielectric contrast/confinement energies.

SUBMITTER: McDonald MP

PROVIDER: S-EPMC5013694 | biostudies-literature | 2016 Aug

REPOSITORIES: biostudies-literature

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Dimensional crossover in semiconductor nanostructures.

McDonald Matthew P MP Chatterjee Rusha R Si Jixin J Jankó Boldizsár B Kuno Masaru M

Nature communications 20160831

Recent advances in semiconductor nanostructure syntheses provide unprecedented control over electronic quantum confinement and have led to extensive investigations of their size- and shape-dependent optical/electrical properties. Notably, spectroscopic measurements show that optical bandgaps of one-dimensional CdSe nanowires are substantially (approximately 100 meV) lower than their zero-dimensional counterparts for equivalent diameters spanning 5-10 nm. But what, exactly, dictates the dimension ...[more]

PMID: 27577091

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